fs: make quota/netlink.c explicitly non-modular

fs: make quota/netlink.c explicitly non-modular

The Kconfig currently controlling compilation of this code is:

config QUOTA_NETLINK_INTERFACE
        bool "Report quota messages through netlink interface"

...meaning that it currently is not being built as a module by anyone.

Lets remove the couple traces of modularity so that when reading the
driver there is no doubt it is builtin-only.

Since module_init translates to device_initcall in the non-modular
case, the init ordering gets bumped to one level earlier when we
use the more appropriate fs_initcall here.  However we've made similar
changes before without any fallout and none is expected here either.

Cc: Jan Kara <jack@suse.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Jan Kara <jack@suse.cz>