ipmi: Fix macro issues

ipmi: Fix macro issues

Macro parameters should almost always have () around them when used.
llvm reported an error on this.

Remove redundant parenthesis and put parenthesis around the entire
macros with assignments in case they are used in an expression.

The macros were doing ((v) & 1) for a binary input, but that only works
if v == 0 or if v & 1.  Changed to !!(v) so they work for all values.

Remove some unused macros.

Reported in https://bugs.launchpad.net/bugs/1651167

An audit of these changes found no semantic changes; this is just
cleanups for proper style and to avoid a compiler warning.

Signed-off-by: Corey Minyard <cminyard@mvista.com>
Reviewed-by: Eric Blake <eblake@redhat.com>