crypto: hifn_795x - Remove unused ctx variable

The below patch gets rid of an unused variable ctx reported by
GCC when building the kernel.
  CC [M]  drivers/crypto/hifn_795x.o
drivers/crypto/hifn_795x.c: In function 'hifn_flush':
drivers/crypto/hifn_795x.c:2021:23: warning: variable 'ctx' set but not used
drivers/crypto/hifn_795x.c: In function 'hifn_process_queue':
drivers/crypto/hifn_795x.c:2142:23: warning: variable 'ctx' set but not used

Signed-off-by: Justin P. Mattock <justinmattock@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>