ixgbe: Fix MRQC register value.

Focus on the MRQE field of the MRQC register, which is 4 bits wide,
and we use these 3 types of values.

• IXGBE_MRQC_RSSEN 0x1 (non VF mode)
• IXGBE_MRQC_VMDQRSS32EN 0xA (less than 33 VFs)
• IXGBE_MRQC_VMDQRSS64EN 0xB (less than 65 VFs)

If we always take a bitwise OR with IXGBE_MRQC_RSSEN,
IXGBE_MRQC_VMDQRSS32EN will never be chosen.
Select these 3 types of values for the proper case.

Signed-off-by: Yuichiro NAITO <naito.yuichiro@gmail.com>

MFC after: 1 week
Pull Request: https://github.com/freebsd/freebsd-src/pull/2132