crypto: xilinx - Updated Makefile for xilinx subdirectory

This patch updates the Makefile for xilinx subdirectory.
CONFIG_CRYPTO_DEV_ZYNQMP_AES protects zynqmp-aes-gcm.o and it is used
twice (in drivers/crypto/Makefile and drivers/crypto/xilinx/Makefile)
and it is enough to use it once.
Signed-off-by: Harsha <harsha.harsha@xilinx.com>
Reviewed-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/crypto/Makefile

@@ -47,7 +47,7 @@ obj-$(CONFIG_CRYPTO_DEV_VMX) += vmx/
 obj-$(CONFIG_CRYPTO_DEV_BCM_SPU) += bcm/
 obj-$(CONFIG_CRYPTO_DEV_SAFEXCEL) += inside-secure/
 obj-$(CONFIG_CRYPTO_DEV_ARTPEC6) += axis/
-obj-$(CONFIG_CRYPTO_DEV_ZYNQMP_AES) += xilinx/
+obj-y += xilinx/
 obj-y += hisilicon/
 obj-$(CONFIG_CRYPTO_DEV_AMLOGIC_GXL) += amlogic/
 obj-y += keembay/