erofs: using switch-case while checking the inode type.

while filling the linux inode, using switch-case statement to check
the type of inode.
switch-case statement looks more clean here.
Signed-off-by: Pratik Shinde <pratikshinde320@gmail.com>
Reviewed-by: Gao Xiang <gaoxiang25@huawei.com>
Link: https://lore.kernel.org/r/20190830095615.10995-1-pratikshinde320@gmail.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

fs/erofs/inode.c

@@ -190,22 +190,28 @@ static int fill_inode(struct inode *inode, int isdir)
 	err = read_inode(inode, data + ofs);
 	if (!err) {
 		/* setup the new inode */
-		if (S_ISREG(inode->i_mode)) {
+		switch (inode->i_mode & S_IFMT) {
+		case S_IFREG:
 			inode->i_op = &erofs_generic_iops;
 			inode->i_fop = &generic_ro_fops;
-		} else if (S_ISDIR(inode->i_mode)) {
+			break;
+		case S_IFDIR:
 			inode->i_op = &erofs_dir_iops;
 			inode->i_fop = &erofs_dir_fops;
-		} else if (S_ISLNK(inode->i_mode)) {
+			break;
+		case S_IFLNK:
 			/* by default, page_get_link is used for symlink */
 			inode->i_op = &erofs_symlink_iops;
 			inode_nohighmem(inode);
-		} else if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode) ||
-			S_ISFIFO(inode->i_mode) || S_ISSOCK(inode->i_mode)) {
+			break;
+		case S_IFCHR:
+		case S_IFBLK:
+		case S_IFIFO:
+		case S_IFSOCK:
 			inode->i_op = &erofs_generic_iops;
 			init_special_inode(inode, inode->i_mode, inode->i_rdev);
 			goto out_unlock;
-		} else {
+		default:
 			err = -EFSCORRUPTED;
 			goto out_unlock;
 		}