VFS: Export dquot_send_warning

Sending a message to userspace in a generic format to warn
of events (e.g. quota exceeded) in the quota subsystem is
a generically useful feature. This patch makes some minor
changes to the send_message function from dquot.c renaming
it quota_send_message, moving it to quota.c and exporting it
for use by filesystems which do not use the dquot code.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
diff --git a/fs/quota/Kconfig b/fs/quota/Kconfig
index 8047e01..353e78a 100644
--- a/fs/quota/Kconfig
+++ b/fs/quota/Kconfig
@@ -17,7 +17,7 @@
 
 config QUOTA_NETLINK_INTERFACE
 	bool "Report quota messages through netlink interface"
-	depends on QUOTA && NET
+	depends on QUOTACTL && NET
 	help
 	  If you say Y here, quota warnings (about exceeding softlimit, reaching
 	  hardlimit, etc.) will be reported through netlink interface. If unsure,