Suppress the warning when copying init.recovery.*.rc.

The file is optional, and we already ignore the cp result.

cp: cannot stat 'out/target/product/taimen/root/init.recovery.*.rc': No such file or directory

Test: `m -j bootimage` with aosp_taimen-userdebug. No more warning.
Change-Id: I815c6e0ff8d432123066cf4a44a8638dc94c96d5