gpio: msm: Make msmgpio a platform device

The gpio driver was not a true platform driver and hence wasn't
supported by device tree. This patch fixes that for non-DT targets
by making sure the device gets added early on during board init.
For DT-targets, adding the gpio-controller property for the device
makes sure the msmgpio device gets probed.
This change is done for all TLMM_v2 targets (msm8660 and future)
TLMM_V1 targets remain unaffected.

Change-Id: I8a55ab1e2af0366b3e6893b334ba2396d2a83190
Signed-off-by: Rohit Vaswani <rvaswani@codeaurora.org>
diff --git a/arch/arm/mach-msm/devices-8960.c b/arch/arm/mach-msm/devices-8960.c
index e07301a..680770e 100644
--- a/arch/arm/mach-msm/devices-8960.c
+++ b/arch/arm/mach-msm/devices-8960.c
@@ -4017,6 +4017,11 @@
 	},
 };
 
+struct platform_device msm_gpio_device = {
+	.name = "msmgpio",
+	.id = -1,
+};
+
 struct platform_device mdm_sglte_device = {
 	.name		= "mdm2_modem",
 	.id		= -1,