chore: update nfsrahead defaults

Updating to the defaults: https://fossies.org/linux/nfs-utils/nfs.conf

Fixes #779

Signed-off-by: Steven Kreitzer <[email protected]>
Signed-off-by: Andrey Smirnov <[email protected]>

Author: buroa

storage/nfsrahead/files/nfs.conf

@@ -1,2 +1,4 @@
 [nfsrahead]
+nfs=15000
+nfs4=16000
 default=128