[lld] Fix warnings

This patch fixes:

  lld/MachO/ObjC.cpp:633:12: error: unused variable 'expectedListSize'
  [-Werror,-Wunused-variable]

  lld/MachO/ObjC.cpp:1034:12: error: unused variable 'newCatDef'
  [-Werror,-Wunused-variable]

GitOrigin-RevId: 6800f422c22ffd672b1e31f0d0a3fa29d19b7a13
diff --git a/MachO/ObjC.cpp b/MachO/ObjC.cpp
index 9b24463..3e26ed5 100644
--- a/MachO/ObjC.cpp
+++ b/MachO/ObjC.cpp
@@ -636,6 +636,7 @@
       /*extra null value*/ target->wordSize;
   assert(expectedListSize == ptrListSym->isec->data.size() &&
          "Protocol list does not match expected size");
+  (void)expectedListSize;
 
   uint32_t off = protocolListHeaderLayout.totalSize;
   for (uint32_t inx = 0; inx < protocolCount; ++inx) {
@@ -1033,6 +1034,7 @@
 
   Defined *newCatDef = emitCategory(extInfo);
   assert(newCatDef && "Failed to create a new category");
+  (void)newCatDef;
 
   for (auto &catInfo : categories)
     catInfo.wasMerged = true;