drm/i915/gvt: Replace roundup with DIV_ROUND_UP

It's a bit redundant for the maths here using roundup.
Suggested-by: Jason Gunthorpe <jgg@nvidia.com>
Tested-by: Terrence Xu <terrence.xu@intel.com>
Signed-off-by: Nicolin Chen <nicolinc@nvidia.com>
Link: https://lore.kernel.org/r/20220723020256.30081-3-nicolinc@nvidia.comSigned-off-by: Alex Williamson <alex.williamson@redhat.com>

drivers/gpu/drm/i915/gvt/kvmgt.c

@@ -231,11 +231,9 @@ static void intel_gvt_cleanup_vgpu_type_groups(struct intel_gvt *gvt)
 static void gvt_unpin_guest_page(struct intel_vgpu *vgpu, unsigned long gfn,
 		unsigned long size)
 {
-	int total_pages;
+	int total_pages = DIV_ROUND_UP(size, PAGE_SIZE);
 	int npage;
 
-	total_pages = roundup(size, PAGE_SIZE) / PAGE_SIZE;
-
 	for (npage = 0; npage < total_pages; npage++) {
 		unsigned long cur_gfn = gfn + npage;
 
@@ -247,12 +245,11 @@ static void gvt_unpin_guest_page(struct intel_vgpu *vgpu, unsigned long gfn,
 static int gvt_pin_guest_page(struct intel_vgpu *vgpu, unsigned long gfn,
 		unsigned long size, struct page **page)
 {
+	int total_pages = DIV_ROUND_UP(size, PAGE_SIZE);
 	unsigned long base_pfn = 0;
-	int total_pages;
 	int npage;
 	int ret;
 
-	total_pages = roundup(size, PAGE_SIZE) / PAGE_SIZE;
 	/*
 	 * We pin the pages one-by-one to avoid allocating a big arrary
 	 * on stack to hold pfns.