Revert "Disable clang-format for objective-C bits in GHOST."

This reverts commit 1cb9612d73.

We can now rely on the clang-format version as it's distributed
with pre-compiled binaries.

intern/ghost/intern/GHOST_SystemCocoa.mm

@@ -357,7 +357,6 @@ extern "C" int GHOST_HACK_getFirstFile(char buf[FIRSTFILEBUFLG])
   }
 }
 
-/* clang-format off */
 #pragma mark Cocoa objects
 
 /**
@@ -500,8 +499,6 @@ extern "C" int GHOST_HACK_getFirstFile(char buf[FIRSTFILEBUFLG])
 
 #pragma mark initialization/finalization
 
-/* clang-format on */
-
 GHOST_SystemCocoa::GHOST_SystemCocoa()
 {
   int mib[2];

intern/ghost/intern/GHOST_WindowCocoa.mm

@@ -34,8 +34,6 @@
 
 #include <sys/sysctl.h>
 
-/* clang-format off */
-
 #pragma mark Cocoa window delegate object
 
 @interface CocoaWindowDelegate : NSObject <NSWindowDelegate>
@@ -288,8 +286,6 @@
 
 #pragma mark initialization / finalization
 
-/* clang-format on */
-
 GHOST_WindowCocoa::GHOST_WindowCocoa(GHOST_SystemCocoa *systemCocoa,
                                      const char *title,
                                      GHOST_TInt32 left,