Staging: vt6656: fix up built-in compilation together with rt2870

Fix this build error:

  drivers/staging/vt6656/built-in.o: In function `rotr1':
  (.text+0x1a878): multiple definition of `rotr1'
  drivers/staging/rt2870/built-in.o:(.text+0x106c2): first defined here
  drivers/staging/vt6656/built-in.o: In function `tkip_sbox':
  (.text+0x1a848): multiple definition of `tkip_sbox'
  drivers/staging/rt2870/built-in.o:(.text+0x10697): first defined here
  drivers/staging/vt6656/built-in.o: In function `xor_32':
  (.text+0x1ec24): multiple definition of `xor_32'
  drivers/staging/rt2870/built-in.o:(.text+0x111c4): first defined here
  drivers/staging/vt6656/built-in.o: In function `xor_128':
  (.text+0x1ec00): multiple definition of `xor_128'
  drivers/staging/rt2870/built-in.o:(.text+0x111dd): first defined here
Signed-off-by: Otavio Salvador <otavio@ossystems.com.br>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/staging/vt6656/aes_ccmp.c

@@ -106,7 +106,7 @@ BYTE dot3_table[256] = {
 
 /*---------------------  Export Functions  --------------------------*/
 
-void xor_128(BYTE *a, BYTE *b, BYTE *out)
+static void xor_128(BYTE *a, BYTE *b, BYTE *out)
 {
 	PDWORD dwPtrA = (PDWORD) a;
 	PDWORD dwPtrB = (PDWORD) b;
@@ -119,7 +119,7 @@ void xor_128(BYTE *a, BYTE *b, BYTE *out)
 }
 
 
-void xor_32(BYTE *a, BYTE *b, BYTE *out)
+static void xor_32(BYTE *a, BYTE *b, BYTE *out)
 {
 	PDWORD dwPtrA = (PDWORD) a;
 	PDWORD dwPtrB = (PDWORD) b;

drivers/staging/vt6656/tkip.c

@@ -129,8 +129,6 @@ const BYTE TKIP_Sbox_Upper[256] = {
 //STKIPKeyManagement  sTKIPKeyTable[MAX_TKIP_KEY];
 
 /*---------------------  Static Functions  --------------------------*/
-unsigned int tkip_sbox(unsigned int index);
-unsigned int rotr1(unsigned int a);
 
 /*---------------------  Export Variables  --------------------------*/
 
@@ -139,7 +137,7 @@ unsigned int rotr1(unsigned int a);
 /* Returns a 16 bit value from a 64K entry table. The Table */
 /* is synthesized from two 256 entry byte wide tables.      */
 /************************************************************/
-unsigned int tkip_sbox(unsigned int index)
+static unsigned int tkip_sbox(unsigned int index)
 {
     unsigned int index_low;
     unsigned int index_high;
@@ -155,7 +153,7 @@ unsigned int tkip_sbox(unsigned int index)
 };
 
 
-unsigned int rotr1(unsigned int a)
+static unsigned int rotr1(unsigned int a)
 {
     unsigned int b;