proc_parse: Invert supported VMA check

It's for more natural adding of new else-if branch for aio.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

proc_parse.c

@@ -488,8 +488,11 @@ int parse_smaps(pid_t pid, struct vm_area_list *vma_area_list, bool use_map_file
 				goto err;
 			}
 
-			if (!S_ISREG(st_buf->st_mode) &&
-			    !(S_ISCHR(st_buf->st_mode) && st_buf->st_rdev == DEVZERO)) {
+			if (S_ISREG(st_buf->st_mode))
+				/* regular file mapping -- supported */;
+			else if (S_ISCHR(st_buf->st_mode) && (st_buf->st_rdev == DEVZERO))
+				/* devzero mapping -- also makes sense */;
+			else {
 				pr_err("Can't handle non-regular mapping on %d's map %#lx\n", pid, start);
 				goto err;
 			}