NTB: fix IDT Kconfig typos/spellos

Fix typos in drivers/ntb/hw/idt/Kconfig.
Use consistent spelling and capitalization.

Fixes: bf2a952d ("NTB: Add IDT 89HPESxNTx PCIe-switches support")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Allen Hubbe <allenbh@gmail.com>
Cc: Serge Semin <fancer.lancer@gmail.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>