mtd: parsers: Fix memory leak in mtd_parser_tplink_safeloader_parse()

In the Linux kernel, the following vulnerability has been resolved:

mtd: parsers: Fix memory leak in mtd_parser_tplink_safeloader_parse()

The function mtd_parser_tplink_safeloader_parse() allocates buf via

mtd_parser_tplink_safeloader_read_table(). If the allocation for

parts[idx].name fails inside the loop, the code jumps to the err_free

label without freeing buf, leading to a memory leak.

Fix this by freeing the temporary buffer buf in the err_free label.

Compile tested only. Issue found using a prototype static analysis tool

and code review.