gconfig: remove misleading parentheses around a condition

When building the kernel with clang, the compiler complains about the
presence of a condition inside two pairs of parentheses:

    scripts/kconfig/gconf.c:917:19: error: equality comparison with
    extraneous parentheses [-Werror,-Wparentheses-equality]
                    } else if ((col == COL_OPTION)) {
                                ~~~~^~~~~~~~~~~~~
    scripts/kconfig/gconf.c:917:19: note: remove extraneous parentheses
    around the comparison to silence this warning
                    } else if ((col == COL_OPTION)) {
                               ~    ^            ~
    scripts/kconfig/gconf.c:917:19: note: use '=' to turn this equality
    comparison into an assignment
                    } else if ((col == COL_OPTION)) {
                                    ^~
                                    =

Silence this warning by removing a level of parentheses.

Signed-off-by: Nicolas Iooss <nicolas.iooss_linux@m4x.org>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>