ssb: drop use of non-existing CONFIG_SSB_DEBUG symbol

ssb: drop use of non-existing CONFIG_SSB_DEBUG symbol

CONFIG_SSB_DEBUG is used in one header file and nowhere else, so
remove it and the now-empty inline function that contained it. Also
remove the call to the empty inline function. The empty "default:"
case is kept to prevent 2 compiler warnings:

  drivers/ssb/main.c:1133:9: warning: enumeration value 'SSB_BUSTYPE_PCMCIA' not handled in switch [-Wswitch]
  drivers/ssb/main.c:1133:9: warning: enumeration value 'SSB_BUSTYPE_SDIO' not handled in switch [-Wswitch]

Reported-by: Ying Sun <sunying@isrc.iscas.ac.cn>
Link: https://lore.kernel.org/lkml/4e8525fe.607e2.18a8ddfdce8.Coremail.sunying@isrc.iscas.ac.cn/
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Michael Büsch <m@bues.ch>
Cc: linux-wireless@vger.kernel.org
Cc: Kalle Valo <kvalo@kernel.org>
Acked-by: Michael Büsch <m@bues.ch>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://msgid.link/20240309224540.22682-1-rdunlap@infradead.org