5632 libm's use of _sse_hw is wrong and unnecessary (in that order)

@@ -48,13 +48,12 @@
 #else
 /*
  * The following variable lives in libc on Solaris 10, where it
  * gets set to a nonzero value at startup time on systems with SSE.
  */
-int _sse_hw = 0;
-#pragma weak _sse_hw
-#define test_sse_hw     &_sse_hw && _sse_hw
+extern int _sse_hw;
+#define test_sse_hw     _sse_hw
 #endif
 
 static int accrued = 0;
 static thread_key_t accrued_key;
 static mutex_t accrued_key_lock = DEFAULTMUTEX;