MFC r326392:
Properly define the VLAN_XXX() function macros to avoid miscompilation when
used inside "if" statements comparing with another value.

Detailed explanation:
"if (a ? b : c != 0)" is not the same like "if ((a ? b : c) != 0)"
which is the expected behaviour of a function macro.

Affects:
toecore, linuxkpi and ibcore.

Reviewed by: kib
Sponsored by: Mellanox Technologies