Convert to new override syntax

This is the result of automated script (0.9.1) conversion:

oe-core/scripts/contrib/convert-overrides.py .

converting the metadata to use ":" as the override character instead of "_".

Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>

meta-oe/recipes-devtools/exprtk/exprtk_git.bb

@@ -17,6 +17,6 @@ do_install() {
 }
 
 # exprtk is a header only C++ library, so the main package will be empty.
-RDEPENDS_${PN}-dev = ""
+RDEPENDS:${PN}-dev = ""
 
 BBCLASSEXTEND = "native nativesdk"