dev-R/*: remove AR export no more needed

Signed-off-by: Alessandro Barbieri <lssndrbarbieri@gmail.com>

dev-R/jsonlite/jsonlite-1.7.2.ebuild

@@ -3,14 +3,10 @@
 
 EAPI=7
 
-inherit R-packages toolchain-funcs
+inherit R-packages
 
 DESCRIPTION='A Simple and Robust JSON Parser and generator for R'
 KEYWORDS="~amd64"
 LICENSE='MIT'
 
 #unbundling status: https://github.com/jeroen/jsonlite/issues/201
-src_prepare() {
-	tc-export AR
-	R-packages_src_prepare
-}