be2net: fix wrong return value in be_check_ufi_compatibility()

In the commit a6e6ff6e
("be2net: simplify UFI compatibility checking"), a return value of "-1"
was incorrectly used in place of "false". This patch fixes it.

Fixes: a6e6ff6e ("be2net: simplify UFI compatibility checking")
Signed-off-by: Vasundhara Volam <vasundhara.volam@avagotech.com>
Signed-off-by: Sathya Perla <sathya.perla@avagotech.com>
Signed-off-by: David S. Miller <davem@davemloft.net>