config: let Automake handle Lex and Yacc dist and cleaning

BUILT_SOURCES and MAINTAINERCLEAN are not needed for lex and yacc
Note that xkbscan was missing on those lines.

Automake generates all the rules to handle building, distribution
and cleaning.

Acked-by: Daniel Stone <daniel@fooishbar.org>
Reviewed-by: Kristian Høgsberg <krh@bitplanet.net>
Signed-off-by: Gaetan Nadon <memsize@videotron.ca>
diff --git a/src/xkbcomp/Makefile.am b/src/xkbcomp/Makefile.am
index 59a49a9..db54c55 100644
--- a/src/xkbcomp/Makefile.am
+++ b/src/xkbcomp/Makefile.am
@@ -2,9 +2,6 @@
 AM_CFLAGS = $(X11_CFLAGS) $(CWARNFLAGS) \
 	-DDFLT_XKB_CONFIG_ROOT='"$(XKBCONFIGROOT)"'
 
-BUILT_SOURCES = xkbparse.c
-MAINTAINERCLEANFILES = $(BUILT_SOURCES)
-
 noinst_LTLIBRARIES = libxkbcomp.la
 libxkbcomp_la_SOURCES = \
 	action.c \