cppcheck: extract update_* to external update file

srcpkgs/cppcheck/template

@@ -7,8 +7,6 @@ short_desc="Static analysis of C/C++ code"
 maintainer="Juan RP <xtraeme@gmail.com>"
 license="GPL-2"
 homepage="http://cppcheck.sourceforge.net"
-update_site="https://api.github.com/repos/danmar/cppcheck/tags"
-update_pattern='"name":\s*"\K[^\d]*([\d\.]+)(?=")'
 
 do_fetch() {
 	git clone -b ${version} git://github.com/danmar/cppcheck ${pkgname}-${version}

srcpkgs/cppcheck/update

@@ -0,0 +1,2 @@
+site="https://api.github.com/repos/danmar/cppcheck/tags"
+pattern='"name":\s*"\K[^\d]*([\d\.]+)(?=")'