msm: camera: Convert VPE into platform device

Make VPE platform devices as well as
v4l2 sub-devices. They are created at system boot-up,
and registered during camera open.

The subdevices are decoupled from the v4l2 devices by
using device model APIs to find and register them.

Change-Id: I884b38f714df6f101d48b38219d274bf91fef4c6
Signed-off-by: Kevin Chan <ktchan@codeaurora.org>
diff --git a/arch/arm/mach-msm/devices.h b/arch/arm/mach-msm/devices.h
index 871a7d3..b5cadd3 100644
--- a/arch/arm/mach-msm/devices.h
+++ b/arch/arm/mach-msm/devices.h
@@ -64,6 +64,7 @@
 extern struct platform_device msm8960_device_csid1;
 extern struct platform_device msm8960_device_ispif;
 extern struct platform_device msm8960_device_vfe;
+extern struct platform_device msm8960_device_vpe;
 
 extern struct platform_device apq8064_device_uart_gsbi1;
 extern struct platform_device apq8064_device_uart_gsbi3;