sc520: fix build warning about unused temp var

Building the eNET_SRAM board fails for me:
	sc520_timer.c: In function 'sc520_udelay':
	sc520_timer.c:81:7: error: variable 'temp' set but not used
		[-Werror=unused-but-set-variable]
	cc1: all warnings being treated as errors
	make[1]: *** [sc520_timer.o] Error 1

Signed-off-by: Mike Frysinger <vapier@gentoo.org>

arch/x86/cpu/sc520/sc520_timer.c

@@ -78,10 +78,9 @@ void sc520_udelay(unsigned long usec)
 {
 	int m = 0;
 	long u;
-	long temp;
 
-	temp = readw(&sc520_mmcr->swtmrmilli);
-	temp = readw(&sc520_mmcr->swtmrmicro);
+	readw(&sc520_mmcr->swtmrmilli);
+	readw(&sc520_mmcr->swtmrmicro);
 
 	do {
 		m += readw(&sc520_mmcr->swtmrmilli);