northbridge/amd/amdmct: Superfluous parenthesis in if-statements

Remove superfluous parenthesis found in some if-statements, spotted by
Clang.

Change-Id: I98d2bf6b408caf320c5bcc8adb23d621b182976b
Signed-off-by: Edward O'Callaghan <eocallaghan@alterapraxis.com>
Reviewed-on: http://review.coreboot.org/5817
Tested-by: build bot (Jenkins)
Reviewed-by: Marc Jones <marc.jones@se-eng.com>
northbridge/amd/amdmct: Incorrect usage of logical over bitwise and

Small mix up of logical/bitwise logical and operation. Spotted by Clang.

Change-Id: I2c2256b9b2f2b6ca627914118c745f579555acc9
Signed-off-by: Edward O'Callaghan <eocallaghan@alterapraxis.com>
Reviewed-on: http://review.coreboot.org/5820
Tested-by: build bot (Jenkins)
Reviewed-by: Marc Jones <marc.jones@se-eng.com>