[OpenMP] Fix extra parenthesis in kmp_os.h

Differential Revision: https://reviews.llvm.org/D143940

(cherry picked from commit 8c74def)

Author: Vadim Paretsky (Intel Americas Inc)

openmp/runtime/src/kmp_os.h

@@ -610,7 +610,7 @@ inline kmp_int32 __kmp_compare_and_store_ptr(void *volatile *p, void *cv,
 #define KMP_XCHG_FIXED8(p, v)                                                  \
   _InterlockedExchange8((volatile kmp_int8 *)(p), (kmp_int8)(v));
 #define KMP_XCHG_FIXED16(p, v) _InterlockedExchange16((p), (v));
-#define KMP_XCHG_REAL64(p, v) __kmp_xchg_real64((p), (v)));
+#define KMP_XCHG_REAL64(p, v) __kmp_xchg_real64((p), (v));
 
 inline kmp_real64 __kmp_xchg_real64(volatile kmp_real64 *p, kmp_real64 v) {
   kmp_int64 tmp = _InterlockedExchange64((volatile kmp_int64 *)p, *(kmp_int64