soc: aspeed: socinfo: Add kfree for kstrdup

soc: aspeed: socinfo: Add kfree for kstrdup

Add kfree() in the later error handling in order to avoid memory leak.

Fixes: e0218dca5787 ("soc: aspeed: Add soc info driver")
Signed-off-by: Jiasheng Jiang <jiasheng@iscas.ac.cn>
Link: https://lore.kernel.org/r/20230707021625.7727-1-jiasheng@iscas.ac.cn
Signed-off-by: Joel Stanley <joel@jms.id.au>
Link: https://lore.kernel.org/r/20230810123104.231167-1-joel@jms.id.au
Signed-off-by: Arnd Bergmann <arnd@arndb.de>