cxgb4: Add cxgb4_debugfs.c, move all debugfs code to new file

Signed-off-by: Hariprasad Shenai <hariprasad@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --cc drivers/net/ethernet/chelsio/cxgb4/Makefile
Simple merge

diff --cc drivers/net/ethernet/chelsio/cxgb4/cxgb4.h
Simple merge

diff --cc drivers/net/ethernet/chelsio/cxgb4/cxgb4_debugfs.c
Simple merge

diff --cc drivers/net/ethernet/chelsio/cxgb4/cxgb4_debugfs.h
Simple merge

diff --cc drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c
Simple merge