udf: replace all adds to little endians variables with le*_add_cpu

replace all:
	little_endian_variable = cpu_to_leX(leX_to_cpu(little_endian_variable) +
	                                    expression_in_cpu_byteorder);
with:
	leX_add_cpu(&little_endian_variable, expression_in_cpu_byteorder);
sparse didn't generate any new warning with this patch

Signed-off-by: Marcin Slusarz <marcin.slusarz@gmail.com
Signed-off-by: Jan Kara <jack@suse.cz>
diff --git a/fs/udf/ialloc.c b/fs/udf/ialloc.c
index c3fb28e..eb9cfa2 100644
--- a/fs/udf/ialloc.c
+++ b/fs/udf/ialloc.c
@@ -46,11 +46,9 @@
 		struct logicalVolIntegrityDescImpUse *lvidiu =
 							udf_sb_lvidiu(sbi);
 		if (S_ISDIR(inode->i_mode))
-			lvidiu->numDirs =
-				cpu_to_le32(le32_to_cpu(lvidiu->numDirs) - 1);
+			le32_add_cpu(&lvidiu->numDirs, -1);
 		else
-			lvidiu->numFiles =
-				cpu_to_le32(le32_to_cpu(lvidiu->numFiles) - 1);
+			le32_add_cpu(&lvidiu->numFiles, -1);
 
 		mark_buffer_dirty(sbi->s_lvid_bh);
 	}
@@ -104,11 +102,9 @@
 		lvhd = (struct logicalVolHeaderDesc *)
 				(lvid->logicalVolContentsUse);
 		if (S_ISDIR(mode))
-			lvidiu->numDirs =
-				cpu_to_le32(le32_to_cpu(lvidiu->numDirs) + 1);
+			le32_add_cpu(&lvidiu->numDirs, 1);
 		else
-			lvidiu->numFiles =
-				cpu_to_le32(le32_to_cpu(lvidiu->numFiles) + 1);
+			le32_add_cpu(&lvidiu->numFiles, 1);
 		iinfo->i_unique = uniqueID = le64_to_cpu(lvhd->uniqueID);
 		if (!(++uniqueID & 0x00000000FFFFFFFFUL))
 			uniqueID += 16;