using xargs for string manipulation is somewhat of an abuse

(and breaks the build on windows/cygwin for some reason, although
running the find/xargs command by itself works just fine)
So just use awk instead and have a nicer solution without breaking the
build

Change-Id: I24b9f52c0b84c2e8019f3f6719a307fe508fb755
(cherry picked from commit faa9a681e730e5028c5fefa90938726ff9abe31d)