KEYS: fix error return code in big_key_instantiate()
KEYS: fix error return code in big_key_instantiate()

Fix to return a negative error code from the error handling
case instead of 0, as done elsewhere in this function.

Signed-off-by: Wei Yongjun <b8f9cab8be13de37b9588aedad10a20fc3a68783@trendmicro.com.cn>
Signed-off-by: David Howells <ebac1d06c1688626821bb0e574a037a7a5354e49@redhat.com>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs