drm: msm: add missing dependencies on OF and COMMON_CLK

The msm gpu drivers depend on both the DT mechanism and the
common clk handling code, if they are not enabled, we get
a number of build errors:

In file included from drivers/gpu/drm/msm/hdmi/hdmi.h:27:0,
                 from drivers/gpu/drm/msm/hdmi/hdmi_bridge.c:18:
drivers/gpu/drm/msm/msm_drv.h:45:24: fatal error: mach/board.h: No such file or directory
 #include <mach/board.h>
                        ^

drivers/gpu/drm/msm/hdmi/hdmi_phy_8960.c:503:2: error: implicit declaration of function 'devm_clk_register' [-Werror=implicit-function-declaration]

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Dave Airlie <airlied@gmail.com>