Fix macOS x64

The assembler was generating 32 bit conditional relative jumps instead
of ones with 8 bit displacement. I've found that a presence of a global
label between the jump site and the destination makes the assembler to
do that. Changing PATCH_LABEL macro fixed it.

src/coreclr/pal/inc/unixasmmacrosamd64.inc

@@ -27,7 +27,7 @@
 
 .macro PATCH_LABEL Name
         .global C_FUNC(\Name)
-C_FUNC(\Name):
+        C_FUNC(\Name) = .
 .endm
 
 .macro LEAF_ENTRY Name, Section