9p: Remove INET dependency

9pfs can run over assorted transports, so it doesn't have an INET
dependency.  Drop it and remove the includes of linux/inet.h.

NET_9P_FD/trans_fd.o builds without INET or UNIX and is usable over
plain file descriptors.  However, tcp and unix functionality is still
built and would generate runtime failures if used.  Add imply INET and
UNIX to NET_9P_FD, so functionality is enabled by default but can still
be explicitly disabled.

This allows configuring 9pfs over Xen with INET and UNIX disabled.
Signed-off-by: Jason Andryuk <jandryuk@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

fs/9p/Kconfig

 # SPDX-License-Identifier: GPL-2.0-only
 config 9P_FS
 	tristate "Plan 9 Resource Sharing Support (9P2000)"
-	depends on INET && NET_9P
+	depends on NET_9P
 	select NETFS_SUPPORT
 	help
 	  If you say Y here, you will get experimental support for

fs/9p/vfs_addr.c

@@ -12,7 +12,6 @@
 #include <linux/file.h>
 #include <linux/stat.h>
 #include <linux/string.h>
-#include <linux/inet.h>
 #include <linux/pagemap.h>
 #include <linux/sched.h>
 #include <linux/swap.h>

fs/9p/vfs_dentry.c

@@ -13,7 +13,6 @@
 #include <linux/pagemap.h>
 #include <linux/stat.h>
 #include <linux/string.h>
-#include <linux/inet.h>
 #include <linux/namei.h>
 #include <linux/sched.h>
 #include <linux/slab.h>

fs/9p/vfs_dir.c

@@ -13,7 +13,6 @@
 #include <linux/stat.h>
 #include <linux/string.h>
 #include <linux/sched.h>
-#include <linux/inet.h>
 #include <linux/slab.h>
 #include <linux/uio.h>
 #include <linux/fscache.h>

fs/9p/vfs_file.c

@@ -14,7 +14,6 @@
 #include <linux/file.h>
 #include <linux/stat.h>
 #include <linux/string.h>
-#include <linux/inet.h>
 #include <linux/list.h>
 #include <linux/pagemap.h>
 #include <linux/utsname.h>

fs/9p/vfs_inode.c

@@ -15,7 +15,6 @@
 #include <linux/pagemap.h>
 #include <linux/stat.h>
 #include <linux/string.h>
-#include <linux/inet.h>
 #include <linux/namei.h>
 #include <linux/sched.h>
 #include <linux/slab.h>

fs/9p/vfs_inode_dotl.c

@@ -13,7 +13,6 @@
 #include <linux/pagemap.h>
 #include <linux/stat.h>
 #include <linux/string.h>
-#include <linux/inet.h>
 #include <linux/namei.h>
 #include <linux/sched.h>
 #include <linux/slab.h>

fs/9p/vfs_super.c

@@ -12,7 +12,6 @@
 #include <linux/file.h>
 #include <linux/stat.h>
 #include <linux/string.h>
-#include <linux/inet.h>
 #include <linux/pagemap.h>
 #include <linux/mount.h>
 #include <linux/sched.h>

net/9p/Kconfig

@@ -17,6 +17,8 @@ if NET_9P
 
 config NET_9P_FD
 	default NET_9P
+	imply INET
+	imply UNIX
 	tristate "9P FD Transport"
 	help
 	  This builds support for transports over TCP, Unix sockets and