drm/arm: make undeclared items static

Make the following items static to avoid clashes with
other parts of the kernel (dev_attr_core_id) or just
silence the following sparse warning:

drivers/gpu/drm/arm/malidp_drv.c:371:24: warning: symbol 'malidp_fb_create' was not declared. Should it be static?
drivers/gpu/drm/arm/malidp_drv.c:494:6: warning: symbol 'malidp_error_stats_dump' was not declared. Should it be static?
drivers/gpu/drm/arm/malidp_drv.c:668:1: warning: symbol 'dev_attr_core_id' was not declared. Should it be static?
Signed-off-by: Ben Dooks (Codethink) <ben.dooks@codethink.co.uk>
Signed-off-by: Liviu Dudau <liviu.dudau@arm.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191017111756.12861-1-ben.dooks@codethink.co.uk

drivers/gpu/drm/arm/malidp_drv.c

@@ -368,7 +368,7 @@ malidp_verify_afbc_framebuffer(struct drm_device *dev, struct drm_file *file,
 	return false;
 }
 
-struct drm_framebuffer *
+static struct drm_framebuffer *
 malidp_fb_create(struct drm_device *dev, struct drm_file *file,
 		 const struct drm_mode_fb_cmd2 *mode_cmd)
 {
@@ -491,7 +491,7 @@ void malidp_error(struct malidp_drm *malidp,
 	spin_unlock_irqrestore(&malidp->errors_lock, irqflags);
 }
 
-void malidp_error_stats_dump(const char *prefix,
+static void malidp_error_stats_dump(const char *prefix,
 				    struct malidp_error_stats error_stats,
 				    struct seq_file *m)
 {
@@ -665,7 +665,7 @@ static ssize_t core_id_show(struct device *dev, struct device_attribute *attr,
 	return snprintf(buf, PAGE_SIZE, "%08x\n", malidp->core_id);
 }
 
-DEVICE_ATTR_RO(core_id);
+static DEVICE_ATTR_RO(core_id);
 
 static int malidp_init_sysfs(struct device *dev)
 {