[lldb/Plugin] s/LLDB_PLUGIN/LLDB_PLUGIN_DEFINE/ (NFC)

Rename LLDB_PLUGIN to LLDB_PLUGIN_DEFINE as Pavel suggested in D73067 to
avoid name conflict.

lldb/source/Plugins/ObjectFile/Mach-O/ObjectFileMachO.cpp

@@ -66,7 +66,7 @@ using namespace lldb;
 using namespace lldb_private;
 using namespace llvm::MachO;
 
-LLDB_PLUGIN(ObjectFileMachO)
+LLDB_PLUGIN_DEFINE(ObjectFileMachO)
 
 // Some structure definitions needed for parsing the dyld shared cache files
 // found on iOS devices.