Renamed a function to make Clang static analysis happy.

"Object leaked: allocated object is returned from a function whose
 name ('cfallocDesc') does not contain 'Copy' or 'Create'.  This violates
 the naming convention rules given in the Memory Management Guide for
 Core Foundation"

(it doesn't actually leak, but okay, it's a reasonable naming convention.)

src/platform_macosx.c

@@ -32,11 +32,11 @@
 /* Wrap PHYSFS_Allocator in a CFAllocator... */
 static CFAllocatorRef cfallocator = NULL;
 
-static CFStringRef cfallocDesc(const void *info)
+static CFStringRef cfallocCopyDesc(const void *info)
 {
     return CFStringCreateWithCString(cfallocator, "PhysicsFS",
                                      kCFStringEncodingASCII);
-} /* cfallocDesc */
+} /* cfallocCopyDesc */
 
 
 static void *cfallocMalloc(CFIndex allocSize, CFOptionFlags hint, void *info)
@@ -65,7 +65,7 @@ int __PHYSFS_platformInit(void)
     /* set up a CFAllocator, so Carbon can use the physfs allocator, too. */
     CFAllocatorContext ctx;
     memset(&ctx, '\0', sizeof (ctx));
-    ctx.copyDescription = cfallocDesc;
+    ctx.copyDescription = cfallocCopyDesc;
     ctx.allocate = cfallocMalloc;
     ctx.reallocate = cfallocRealloc;
     ctx.deallocate = cfallocFree;