PCMCIA: add Kconfig control for building sa11xx_base.c

sa11xx_base.c is currently built when either PCMCIA_SA1100 or
PCMCIA_SA1111 are selected.  Let's move the logic into Kconfig.

Acked-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/drivers/pcmcia/Makefile b/drivers/pcmcia/Makefile
index ec543a4..05136dd 100644
--- a/drivers/pcmcia/Makefile
+++ b/drivers/pcmcia/Makefile
@@ -25,8 +25,9 @@
 obj-$(CONFIG_TCIC)				+= tcic.o
 obj-$(CONFIG_PCMCIA_M8XX)			+= m8xx_pcmcia.o
 obj-$(CONFIG_PCMCIA_SOC_COMMON)			+= soc_common.o
-obj-$(CONFIG_PCMCIA_SA1100)			+= sa11xx_base.o sa1100_cs.o
-obj-$(CONFIG_PCMCIA_SA1111)			+= sa11xx_base.o sa1111_cs.o
+obj-$(CONFIG_PCMCIA_SA11XX_BASE)		+= sa11xx_base.o
+obj-$(CONFIG_PCMCIA_SA1100)			+= sa1100_cs.o
+obj-$(CONFIG_PCMCIA_SA1111)			+= sa1111_cs.o
 obj-$(CONFIG_M32R_PCC)				+= m32r_pcc.o
 obj-$(CONFIG_M32R_CFC)				+= m32r_cfc.o
 obj-$(CONFIG_PCMCIA_BCM63XX)			+= bcm63xx_pcmcia.o