drm/msm/adreno: move function declarations to header file

We get 2 warnings when building kernel with W=1:
drivers/gpu/drm/msm/adreno/a3xx_gpu.c:535:17: warning: no previous prototype for 'a3xx_gpu_init' [-Wmissing-prototypes]
drivers/gpu/drm/msm/adreno/a4xx_gpu.c:624:17: warning: no previous prototype for 'a4xx_gpu_init' [-Wmissing-prototypes]

In fact, both functions are declared in
drivers/gpu/drm/msm/adreno/adreno_device.c, but should be declared
in a header file. So this patch moves both function declarations to
drivers/gpu/drm/msm/adreno/adreno_gpu.h.

Signed-off-by: Baoyou Xie <baoyou.xie@linaro.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1477127865-9381-1-git-send-email-baoyou.xie@linaro.org

drivers/gpu/drm/msm/adreno/adreno_device.c

@@ -25,9 +25,6 @@ bool hang_debug = false;
 MODULE_PARM_DESC(hang_debug, "Dump registers when hang is detected (can be slow!)");
 module_param_named(hang_debug, hang_debug, bool, 0600);
 
-struct msm_gpu *a3xx_gpu_init(struct drm_device *dev);
-struct msm_gpu *a4xx_gpu_init(struct drm_device *dev);
-
 static const struct adreno_info gpulist[] = {
 	{
 		.rev   = ADRENO_REV(3, 0, 5, ANY_ID),

drivers/gpu/drm/msm/adreno/adreno_gpu.h

@@ -311,4 +311,7 @@ static inline void adreno_gpu_write(struct adreno_gpu *gpu,
 		gpu_write(&gpu->base, reg - 1, data);
 }
 
+struct msm_gpu *a3xx_gpu_init(struct drm_device *dev);
+struct msm_gpu *a4xx_gpu_init(struct drm_device *dev);
+
 #endif /* __ADRENO_GPU_H__ */