tipc: rename the module name diag to tipc_diag

It is not appropriate for TIPC to use "diag" as its diag module name
while the other protocols are using "$(protoname)_diag" like tcp_diag,
udp_diag and sctp_diag etc.

So this patch is to rename diag.ko to tipc_diag.ko in tipc's Makefile.

Signed-off-by: Xin Long <[e-mail]>
Reviewed-by: Tung Nguyen <[e-mail]>
Link: https://lore.kernel.org/r/d9[e-mail]
Signed-off-by: Paolo Abeni <[e-mail]>

net/tipc/Makefile

···
 tipc-$(CONFIG_SYSCTL)		+= sysctl.o
 tipc-$(CONFIG_TIPC_CRYPTO)	+= crypto.o
 
-
-obj-$(CONFIG_TIPC_DIAG)	+= diag.o
+obj-$(CONFIG_TIPC_DIAG)	+= tipc_diag.o
+tipc_diag-y	+= diag.o