drm/gma500/gem: Add and rename some function parameter descriptions

Fixes the following W=1 kernel build warning(s):

 drivers/gpu/drm/gma500/gem.c:57:5: warning: no previous prototype for ‘psb_gem_create’ [-Wmissing-prototypes]
 drivers/gpu/drm/gma500/gem.c:59: warning: Function parameter or member 'stolen' not described in 'psb_gem_create'
 drivers/gpu/drm/gma500/gem.c:59: warning: Function parameter or member 'align' not described in 'psb_gem_create'
 drivers/gpu/drm/gma500/gem.c:110: warning: Function parameter or member 'file' not described in 'psb_gem_dumb_create'
 drivers/gpu/drm/gma500/gem.c:110: warning: Excess function parameter 'drm_file' description in 'psb_gem_dumb_create'
 drivers/gpu/drm/gma500/gem.c:135: warning: Excess function parameter 'vma' description in 'psb_gem_fault'

Cc: Patrik Jakobsson <patrik.r.jakobsson@gmail.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: dri-devel@lists.freedesktop.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210115181313.3431493-16-lee.jones@linaro.org

drivers/gpu/drm/gma500/gem.c

@@ -49,6 +49,8 @@ const struct drm_gem_object_funcs psb_gem_object_funcs = {
  *	@dev: our device
  *	@size: the size requested
  *	@handlep: returned handle (opaque number)
+ *	@stolen: unused
+ *	@align: unused
  *
  *	Create a GEM object, fill in the boilerplate and attach a handle to
  *	it so that userspace can speak about it. This does the core work
@@ -97,7 +99,7 @@ int psb_gem_create(struct drm_file *file, struct drm_device *dev, u64 size,
 
 /**
  *	psb_gem_dumb_create	-	create a dumb buffer
- *	@drm_file: our client file
+ *	@file: our client file
  *	@dev: our device
  *	@args: the requested arguments copied from userspace
  *
@@ -116,7 +118,6 @@ int psb_gem_dumb_create(struct drm_file *file, struct drm_device *dev,
 
 /**
  *	psb_gem_fault		-	pagefault handler for GEM objects
- *	@vma: the VMA of the GEM object
  *	@vmf: fault detail
  *
  *	Invoked when a fault occurs on an mmap of a GEM managed area. GEM