firmware: Google VPD: Fix memory allocation error handling
This patch fixes several issues:
- if the 1st 'kzalloc' fails, we dereference a NULL pointer
- if the 2nd 'kzalloc' fails, there is a memory leak
- if 'sysfs_create_bin_file' fails there is also a memory leak
Fix it by adding a test after the first memory allocation and some error
handling paths to correctly free memory if needed.