Makefile.defs: version set to 4.2.0-rc0

- branch for release series 4.2.x

Makefile.defs

@@ -165,7 +165,7 @@ INSTALL_FLAVOUR=$(FLAVOUR)
 VERSION = 4
 PATCHLEVEL = 2
 SUBLEVEL =  0
-EXTRAVERSION = -pre1
+EXTRAVERSION = -rc0
 
 # memory manager switcher
 # 0 - f_malloc (fast malloc)