misc: Remove autotools_stage as it was removed in master

autotools_stage has only included autotools at least in dora and
later and we can simply change this.
diff --git a/recipes-osmocom/libosmocore/libosmocore.inc b/recipes-osmocom/libosmocore/libosmocore.inc
index c0dba30..de5742f 100644
--- a/recipes-osmocom/libosmocore/libosmocore.inc
+++ b/recipes-osmocom/libosmocore/libosmocore.inc
@@ -6,5 +6,5 @@
 
 LIC_FILES_CHKSUM = "file://COPYING;md5=751419260aa954499f7abaabaa882bbe"
 
-inherit autotools_stage pkgconfig
+inherit autotools pkgconfig