crypto: vmx - Fixing GHASH Key issue on little endian

GHASH table algorithm is using a big endian key.
In little endian machines key will be LE ordered.
After a lxvd2x instruction key is loaded as it is,
LE/BE order, in first case it'll generate a wrong
table resulting in wrong hashes from the algorithm.

Bug affects only LE machines.
In order to fix it we do a swap for loaded key.

Cc: stable@vger.kernel.org
Signed-off-by: Leonidas S Barbosa <leosilva@linux.vnet.ibm.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/crypto/vmx/ghashp8-ppc.pl

@@ -61,6 +61,12 @@ $code=<<___;
 	mtspr		256,r0
 	li		r10,0x30
 	lvx_u		$H,0,r4			# load H
+	le?xor		r7,r7,r7
+	le?addi		r7,r7,0x8		# need a vperm start with 08
+	le?lvsr		5,0,r7
+	le?vspltisb	6,0x0f
+	le?vxor		5,5,6			# set a b-endian mask
+	le?vperm	$H,$H,$H,5
 
 	vspltisb	$xC2,-16		# 0xf0
 	vspltisb	$t0,1			# one