pinctrl: renesas: Rename RZ/A1 R7S72100 PFC tables to RZ/A1

Rename pfc-r7s72100.c to pfc-rza1.c to match the file name with Linux.
Rename the Kconfig symbol to match.

No functional change.

Signed-off-by: Marek Vasut <marek.vasut+renesas@mailbox.org>
diff --git a/drivers/pinctrl/renesas/Kconfig b/drivers/pinctrl/renesas/Kconfig
index 0ea39b4..32f44e5 100644
--- a/drivers/pinctrl/renesas/Kconfig
+++ b/drivers/pinctrl/renesas/Kconfig
@@ -131,7 +131,7 @@
 	help
 	  Support pin multiplexing control on Renesas RCar Gen4 R8A779G0 SoCs.
 
-config PINCTRL_PFC_R7S72100
+config PINCTRL_RZA1
 	bool "Renesas RZ/A1 R7S72100 pin control driver"
 	depends on CPU_RZA1
 	default y if CPU_RZA1