Core Update 173: Ship grep

Signed-off-by: Peter Müller <peter.mueller@ipfire.org>

diff --git a/config/rootfiles/core/173/filelists/grep b/config/rootfiles/core/173/filelists/grep
new file mode 120000 (symlink)
index 0000000..ab5ef8b
--- /dev/null
+++ b/config/rootfiles/core/173/filelists/grep
@@ -0,0 +1 @@
+../../../common/grep
\ No newline at end of file