keycodes: fix valgrind warnings

keycodes: fix valgrind warnings

==7071== Conditional jump or move depends on uninitialised value(s)
==7071==    at 0x40B6CB: AddIndicatorName (keycodes.c:148)
==7071==    by 0x40C34F: MergeIncludedKeycodes (keycodes.c:420)
==7071==    by 0x40C613: HandleIncludeKeycodes (keycodes.c:480)
==7071==    by 0x40D022: HandleKeycodesFile (keycodes.c:733)
==7071==    by 0x40D79F: CompileKeycodes (keycodes.c:881)
==7071==    by 0x401E22: compile_keymap (xkbcomp.c:157)
==7071==    by 0x402091: xkb_map_new_from_kccgst (xkbcomp.c:229)
==7071==    by 0x40216A: xkb_map_new_from_names (xkbcomp.c:254)
==7071==    by 0x4046F5: test_compile_rules (common.c:164)
==7071==    by 0x4015C1: test_rmlvo (rulescomp.c:44)
==7071==    by 0x40180D: main (rulescomp.c:98)

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