[acc][flang] Add isDeviceData APIs for device data detection (#176219)

Add comprehensive APIs to detect device-resident data across OpenACC
type and operation interfaces. This enables passes to identify data that
is already on the device (e.g., CUF device/managed/constant memory, GPU
address spaces) and handle it appropriately.

New interface methods:
- PointerLikeType::isDeviceData(Value): Returns true if the pointer
points to device data.
- MappableType::isDeviceData(Value): Returns true if the variable
represents device data.
- GlobalVariableOpInterface::isDeviceData(): Returns true if the global
variable is device data.

New utilities in OpenACCUtils:
- acc::isDeviceValue(Value): Checks if a value represents device data by
querying type interfaces, PartialEntityAccessOpInterface for base
entities, and AddressOfGlobalOpInterface for global symbols.
- acc::isValidValueUse(Value, Region): Checks if a value is legal in an
OpenACC region by verifying it comes from a data operation, is only used
by private clauses, or is device data.

Updated isValidSymbolUse to check
GlobalVariableOpInterface::isDeviceData()
for symbols referencing device-resident globals.

FIR implementations check for CUF data attributes (device, managed,
constant, shared, unified) on operations, block arguments, and globals.
The implementation traces through fir.rebox, fir.embox, fir.declare,
hlfir.declare, and fir.address_of to find the underlying data source.

Memref implementations check for gpu::AddressSpaceAttr on the memref
type.

Updated ACCImplicitData to use acc::isDeviceValue for generating
acc.deviceptr clauses for device-resident data instead of
copyin/copyout.

Updated OpenACCSupport::isValidValueUse to fallback to the new
acc::isValidValueUse utility.