crypto: vmx - drop unexpected word 'for' in comments

there is an unexpected word 'for' in the comments that need to be dropped

file - drivers/crypto/vmx/ghashp8-ppc.pl
line - 19

"# GHASH for for PowerISA v2.07."

changed to:

"# GHASH for PowerISA v2.07."
Signed-off-by: NJiang Jian <jiangjian@cdjrlc.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

drivers/crypto/vmx/ghashp8-ppc.pl

@@ -16,7 +16,7 @@
 # details see https://www.openssl.org/~appro/cryptogams/.
 # ====================================================================
 #
-# GHASH for for PowerISA v2.07.
+# GHASH for PowerISA v2.07.
 #
 # July 2014
 #