tests: rgw/singleton: drop duplicate filestore-xfs.yaml

This yaml is now included in the objectstore/ directory. It makes no sense to
duplicate it here.

Signed-off-by: Nathan Cutler <ncutler@suse.com>

diff --git a/qa/suites/rgw/singleton/filestore-xfs.yaml b/qa/suites/rgw/singleton/filestore-xfs.yaml
deleted file mode 120000 (symlink)
index 59ef7e4..0000000
--- a/qa/suites/rgw/singleton/filestore-xfs.yaml
+++ /dev/null
@@ -1 +0,0 @@
-../../../objectstore/filestore-xfs.yaml
\ No newline at end of file