fix error in previous ld80 fpclassify commit

src/math/__fpclassifyl.c

@@ -7,7 +7,7 @@ int __fpclassifyl(long double __x)
 	union {
 		long double __ld;
 		__uint16_t __hw[5];
-		__int64_t __m;
+		int64_t __m;
 	} __y = { __x };
 	int __ee = __y.__hw[4]&0x7fff;
 	if (!__ee) return __y.__m ? FP_SUBNORMAL : FP_ZERO;