kconfig: fix compatibility with older flex versions

Older flex versions require there be no space between options and
their arguments. For example '-P zconf' is not correct and should
be '-Pzconf'. This is for example the case for flex-2.5.4 shipped
with CentOS 5.8.

Signed-off-by: Thomas De Schampheleire <thomas.de.schampheleire@gmail.com>
Message-Id: <9652ce148bddc1def484.1339241000@beantl019720>

kconfig/Makefile

@@ -88,7 +88,7 @@ zconf.hash.c: zconf.gperf
 
 lex.zconf.c: zconf.l
 	@echo "  LEX    '$@'"
-	@flex -L -P zconf -o $@ $<
+	@flex -L -Pzconf -o$@ $<
 
 # Build C files
 %.o: %.c