msm: board-8064: Create a separate board file for gpiomux

Move the APQ8064 gpiomux configuration to a dedicated board
file.

Change-Id: Ifb849aa64192f198a3781be2e4d80702b77c7607
Signed-off-by: Stepan Moskovchenko <stepanm@codeaurora.org>
diff --git a/arch/arm/mach-msm/board-8064.h b/arch/arm/mach-msm/board-8064.h
index d9da00a..a56bf31 100644
--- a/arch/arm/mach-msm/board-8064.h
+++ b/arch/arm/mach-msm/board-8064.h
@@ -42,4 +42,5 @@
 		struct mmc_platform_data *plat);
 
 void apq8064_init_mmc(void);
+void apq8064_init_gpiomux(void);
 #endif