ACPICA: debugger: dbconvert: free pld_info on error return path

ACPICA commit 23e644670539e23818fa81e2af5e89ad6657e75c

A failed allocation of new_buffer causes a leak of pld_info
because the error return path fails to free pld_info. Ensure
it is freed on the error exit path.

Link: https://github.com/acpica/acpica/commit/23e64467


Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>