Use __GNUC_PREREQ rather than __GNUC_PREREQ__ to match glibc.

Bug: 16874785
Change-Id: I8512f8be3fd149d8720c5c3b4657bedd5ce2b1d1
diff --git a/libm/include/math.h b/libm/include/math.h
index c51f3af..1fcc578 100644
--- a/libm/include/math.h
+++ b/libm/include/math.h
@@ -36,11 +36,11 @@
 	float		__uf;
 } __nan;
 
-#if __GNUC_PREREQ__(3, 3) || (defined(__INTEL_COMPILER) && __INTEL_COMPILER >= 800)
+#if __GNUC_PREREQ(3, 3) || (defined(__INTEL_COMPILER) && __INTEL_COMPILER >= 800)
 #define	__MATH_BUILTIN_CONSTANTS
 #endif
 
-#if __GNUC_PREREQ__(3, 0) && !defined(__INTEL_COMPILER)
+#if __GNUC_PREREQ(3, 0) && !defined(__INTEL_COMPILER)
 #define	__MATH_BUILTIN_RELOPS
 #endif