perl: update version in include file

mk/perl.mk

@@ -1,4 +1,4 @@
-PERL_VERSION=5.38.0
+PERL_VERSION=5.40.2
 PERL_ARCHNAME:=$(ADK_TARGET_CPU_ARCH)-linux
 PERL_SITEDIR:=/usr/lib/perl5/site_perl/$(PERL_VERSION)
 PERL_INCDIR:=/usr/lib/perl5/$(PERL_VERSION)/$(PERL_ARCHNAME)/CORE