board/cm4008/flash.c: Fix GCC 4.6 warnings

Fix:
flash.c: In function 'flash_erase':
flash.c:209:6: warning: variable 'flag' set but not used
[-Wunused-but-set-variable]
flash.c: In function 'write_data':
flash.c:373:6: warning: variable 'flag' set but not used
[-Wunused-but-set-variable]

Signed-off-by: Anatolij Gustschin <agust@denx.de>
diff --git a/board/cm4008/flash.c b/board/cm4008/flash.c
index 2e1356f..5522bf0 100644
--- a/board/cm4008/flash.c
+++ b/board/cm4008/flash.c
@@ -206,7 +206,7 @@
 
 int flash_erase (flash_info_t * info, int s_first, int s_last)
 {
-	int flag, prot, sect;
+	int prot, sect;
 	ulong type;
 	int rcode = 0;
 	ulong start;
@@ -240,7 +240,7 @@
 		printf ("\n");
 
 	/* Disable interrupts which might cause a timeout here */
-	flag = disable_interrupts ();
+	disable_interrupts();
 
 	/* Start erase on unprotected sectors */
 	for (sect = s_first; sect <= s_last; sect++) {
@@ -370,7 +370,6 @@
 {
 	volatile unsigned char *addr = (volatile unsigned char *) dest;
 	ulong status;
-	int flag;
 	ulong start;
 
 	/* Check if Flash is (sufficiently) erased */
@@ -380,7 +379,7 @@
 		return (2);
 	}
 	/* Disable interrupts which might cause a timeout here */
-	flag = disable_interrupts ();
+	disable_interrupts();
 
 	*addr = 0x40;	/* write setup */
 	*addr = data;