[llvm-objcopy] Fix some namespace style issues

Similar to https://reviews.llvm.org/D104693
diff --git a/llvm/lib/ObjCopy/Archive.cpp b/llvm/lib/ObjCopy/Archive.cpp
index a221c64..a4e90ce 100644
--- a/llvm/lib/ObjCopy/Archive.cpp
+++ b/llvm/lib/ObjCopy/Archive.cpp
@@ -14,13 +14,13 @@
 #include "llvm/Support/FileOutputBuffer.h"
 #include "llvm/Support/SmallVectorMemoryBuffer.h"
 
-namespace llvm {
-namespace objcopy {
-
+using namespace llvm;
+using namespace llvm::objcopy;
 using namespace llvm::object;
 
 Expected<std::vector<NewArchiveMember>>
-createNewArchiveMembers(const MultiFormatConfig &Config, const Archive &Ar) {
+objcopy::createNewArchiveMembers(const MultiFormatConfig &Config,
+                                 const Archive &Ar) {
   std::vector<NewArchiveMember> NewArchiveMembers;
   Error Err = Error::success();
   for (const Archive::Child &Child : Ar.children(Err)) {
@@ -94,8 +94,8 @@
   return Error::success();
 }
 
-Error executeObjcopyOnArchive(const MultiFormatConfig &Config,
-                              const object::Archive &Ar) {
+Error objcopy::executeObjcopyOnArchive(const MultiFormatConfig &Config,
+                                       const object::Archive &Ar) {
   Expected<std::vector<NewArchiveMember>> NewArchiveMembersOrErr =
       createNewArchiveMembers(Config, Ar);
   if (!NewArchiveMembersOrErr)
@@ -107,6 +107,3 @@
                           Ar.kind(), CommonConfig.DeterministicArchives,
                           Ar.isThin());
 }
-
-} // end namespace objcopy
-} // end namespace llvm
diff --git a/llvm/lib/ObjCopy/CommonConfig.cpp b/llvm/lib/ObjCopy/CommonConfig.cpp
index 1da0240..569e4c3 100644
--- a/llvm/lib/ObjCopy/CommonConfig.cpp
+++ b/llvm/lib/ObjCopy/CommonConfig.cpp
@@ -9,8 +9,8 @@
 #include "llvm/ObjCopy/CommonConfig.h"
 #include "llvm/Support/Errc.h"
 
-namespace llvm {
-namespace objcopy {
+using namespace llvm;
+using namespace llvm::objcopy;
 
 Expected<NameOrPattern>
 NameOrPattern::create(StringRef Pattern, MatchStyle MS,
@@ -47,6 +47,3 @@
   }
   llvm_unreachable("Unhandled llvm.objcopy.MatchStyle enum");
 }
-
-} // end namespace objcopy
-} // end namespace llvm
diff --git a/llvm/lib/ObjCopy/ConfigManager.cpp b/llvm/lib/ObjCopy/ConfigManager.cpp
index 79bbb28..9a81b51 100644
--- a/llvm/lib/ObjCopy/ConfigManager.cpp
+++ b/llvm/lib/ObjCopy/ConfigManager.cpp
@@ -10,8 +10,8 @@
 #include "llvm/Support/Errc.h"
 #include "llvm/Support/Error.h"
 
-namespace llvm {
-namespace objcopy {
+using namespace llvm;
+using namespace llvm::objcopy;
 
 Expected<const COFFConfig &> ConfigManager::getCOFFConfig() const {
   if (!Common.SplitDWO.empty() || !Common.SymbolsPrefix.empty() ||
@@ -107,6 +107,3 @@
 
   return XCOFF;
 }
-
-} // end namespace objcopy
-} // end namespace llvm
diff --git a/llvm/lib/ObjCopy/ObjCopy.cpp b/llvm/lib/ObjCopy/ObjCopy.cpp
index 54dab11..d9a190d 100644
--- a/llvm/lib/ObjCopy/ObjCopy.cpp
+++ b/llvm/lib/ObjCopy/ObjCopy.cpp
@@ -26,15 +26,13 @@
 #include "llvm/Object/Wasm.h"
 #include "llvm/Object/XCOFFObjectFile.h"
 
-namespace llvm {
-namespace objcopy {
-
+using namespace llvm;
 using namespace llvm::object;
 
 /// The function executeObjcopyOnBinary does the dispatch based on the format
 /// of the input binary (ELF, MachO or COFF).
-Error executeObjcopyOnBinary(const MultiFormatConfig &Config,
-                             object::Binary &In, raw_ostream &Out) {
+Error objcopy::executeObjcopyOnBinary(const MultiFormatConfig &Config,
+                                      object::Binary &In, raw_ostream &Out) {
   if (auto *ELFBinary = dyn_cast<object::ELFObjectFileBase>(&In)) {
     Expected<const ELFConfig &> ELFConfig = Config.getELFConfig();
     if (!ELFConfig)
@@ -83,6 +81,3 @@
   return createStringError(object_error::invalid_file_type,
                            "unsupported object file format");
 }
-
-} // end namespace objcopy
-} // end namespace llvm