staging: rtl8188eu: fix null dereference when kzalloc fails

staging: rtl8188eu: fix null dereference when kzalloc fails

If kzalloc() returns NULL, the error path doesn't stop the flow of
control from entering rtw_hal_read_chip_version() which dereferences the
null pointer. Fix this by adding a 'goto' to the error path to more
gracefully handle the issue and avoid proceeding with initialization
steps that we're no longer prepared to handle.

Also update the debug message to be more consistent with the other debug
messages in this function.

Addresses-Coverity: ("Dereference after null check")

Signed-off-by: Connor Kuehl <connor.kuehl@canonical.com>
Link: https://lore.kernel.org/r/20190927214415.899-1-connor.kuehl@canonical.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>