crypto: vmx - fix copy-paste error in CTR mode

The original assembly imported from OpenSSL has two copy-paste
errors in handling CTR mode. When dealing with a 2 or 3 block tail,
the code branches to the CBC decryption exit path, rather than to
the CTR exit path.

This leads to corruption of the IV, which leads to subsequent blocks
being corrupted.

This can be detected with libkcapi test suite, which is available at
https://github.com/smuellerDD/libkcapiReported-by: NOndrej Mosnáček <omosnacek@gmail.com>
Fixes: 5c380d62 ("crypto: vmx - Add support for VMS instructions by ASM")
Cc: stable@vger.kernel.org
Signed-off-by: NDaniel Axtens <dja@axtens.net>
Tested-by: NMichael Ellerman <mpe@ellerman.id.au>
Tested-by: NOndrej Mosnacek <omosnacek@gmail.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

drivers/crypto/vmx/aesp8-ppc.pl

@@ -1854,7 +1854,7 @@ Lctr32_enc8x_three:
 	stvx_u		$out1,$x10,$out
 	stvx_u		$out2,$x20,$out
 	addi		$out,$out,0x30
-	b		Lcbc_dec8x_done
+	b		Lctr32_enc8x_done
 
 .align	5
 Lctr32_enc8x_two:
@@ -1866,7 +1866,7 @@ Lctr32_enc8x_two:
 	stvx_u		$out0,$x00,$out
 	stvx_u		$out1,$x10,$out
 	addi		$out,$out,0x20
-	b		Lcbc_dec8x_done
+	b		Lctr32_enc8x_done
 
 .align	5
 Lctr32_enc8x_one: