ext4: remove unused assignments

The eh assignment in these two places is meaningless, because the
function will goto to merge, which will not use eh.

The clang_analyzer complains as follows:

fs/ext4/extents.c:1988:4 warning:
fs/ext4/extents.c:2016:4 warning:

Value stored to 'eh' is never read
Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: luo penghao <luo.penghao@zte.com.cn>
Link: https://lore.kernel.org/r/20211104064007.2919-1-luo.penghao@zte.comSigned-off-by: Theodore Ts'o <tytso@mit.edu>

fs/ext4/extents.c

@@ -2025,7 +2025,6 @@ int ext4_ext_insert_extent(handle_t *handle, struct inode *inode,
 					+ ext4_ext_get_actual_len(newext));
 			if (unwritten)
 				ext4_ext_mark_unwritten(ex);
-			eh = path[depth].p_hdr;
 			nearex = ex;
 			goto merge;
 		}
@@ -2054,7 +2053,6 @@ int ext4_ext_insert_extent(handle_t *handle, struct inode *inode,
 					+ ext4_ext_get_actual_len(newext));
 			if (unwritten)
 				ext4_ext_mark_unwritten(ex);
-			eh = path[depth].p_hdr;
 			nearex = ex;
 			goto merge;
 		}