pinctrl: renesas: Enable R8A774A1 PFC tables

The PFC tables for the R8A774A1 are already available, but they
not enabled.

This patch adds the Kconfig option and builds the corresponding file
when PINCTRL_PFC_R8A774A1 is enabled.

Signed-off-by: Adam Ford <aford173@gmail.com>
diff --git a/drivers/pinctrl/renesas/Makefile b/drivers/pinctrl/renesas/Makefile
index a92f787..a4eb912 100644
--- a/drivers/pinctrl/renesas/Makefile
+++ b/drivers/pinctrl/renesas/Makefile
@@ -1,4 +1,5 @@
 obj-$(CONFIG_PINCTRL_PFC) += pfc.o
+obj-$(CONFIG_PINCTRL_PFC_R8A774A1) += pfc-r8a7796.o
 obj-$(CONFIG_PINCTRL_PFC_R8A7790) += pfc-r8a7790.o
 obj-$(CONFIG_PINCTRL_PFC_R8A7791) += pfc-r8a7791.o
 obj-$(CONFIG_PINCTRL_PFC_R8A7792) += pfc-r8a7792.o