fcoe: Add runtime debug logging with module parameter debug_logging

This patch converts all FC_DBG statements to use new runtime tunable
debug macros. The fcoe.ko module now has a debug_logging module
parameter.

fcoe_debug_logging is an unsigned integer representing a bitmask of all
available logging levels. Currently only two logging levels are
supported-

   bit
LSB 0 = general fcoe logging
    1 = netdevice related logging

This patch also attempts to clean up some debug statement formatting
so it's more readable.

Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>