state: fix bad EFFECTIVE check in *_is_active()

state: fix bad EFFECTIVE check in *_is_active()

This is a regression introduced in ed78fbcb30888cbfc6cd00.
XKB_STATE_EFFECTIVE is just a OR of the other states, so using & here is
completely wrong. So test/state shows for example:
    dumping state for LCtrl down:
            group English (US) (0): effective depressed latched locked
            mod Control (2): depressed latched locked
    dumping state for LCtrl + RAlt down:
            group English (US) (0): effective depressed latched locked
            mod Control (2): depressed latched locked
            mod Mod1 (3): depressed latched locked
    dumping state for RAlt down:
            group English (US) (0): effective depressed latched locked
            mod Mod1 (3): depressed latched locked
    dumping state for Caps Lock:
            group English (US) (0): effective depressed latched locked
            mod Lock (1): depressed latched locked
            led Caps Lock (0): active
    dumping state for Alt-Shift-+
            group English (US) (0): effective depressed latched locked
            mod Shift (0): depressed latched locked
            mod Mod1 (3): depressed latched locked
which is bogus.

Signed-off-by: Ran Benita <ran234@gmail.com>