drm/ttm: remove comment referencing now-removed vmf_insert_mixed_prot()

This function no longer exists, however the prot != vma->vm_page_prot case
discussion has been retained and moved to vmf_insert_pfn_prot() so refer
to this instead.

Link: https://lkml.kernel.org/r/db403b3622b94a87bd93528cc1d6b44ae88adcdd.1678661628.git.lstoakes@gmail.com
Signed-off-by: Lorenzo Stoakes <[email protected]>
Reviewed-by: Christian König <[email protected]>
Cc: Dan Williams <[email protected]>
Cc: Jason Gunthorpe <[email protected]>
Cc: Kirill A. Shutemov <[email protected]>
Cc: Matthew Wilcox (Oracle) <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: Thomas Hellström <[email protected]>
Cc: Aaron Tomlin <[email protected]>
Cc: Christoph Lameter <[email protected]>
Cc: Frederic Weisbecker <[email protected]>
Cc: Heiko Carstens <[email protected]>
Cc: Huacai Chen <[email protected]>
Cc: Marcelo Tosatti <[email protected]>
Cc: Peter Xu <[email protected]>
Cc: "Russell King (Oracle)" <[email protected]>
Cc: Vlastimil Babka <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

drivers/gpu/drm/ttm/ttm_bo_vm.c

@@ -254,7 +254,7 @@ vm_fault_t ttm_bo_vm_fault_reserved(struct vm_fault *vmf,
 		 * encryption bits. This is because the exact location of the
 		 * data may not be known at mmap() time and may also change
 		 * at arbitrary times while the data is mmap'ed.
-		 * See vmf_insert_mixed_prot() for a discussion.
+		 * See vmf_insert_pfn_prot() for a discussion.
 		 */
 		ret = vmf_insert_pfn_prot(vma, address, pfn, prot);