m68k: Let GENERIC_IOMAP depend on HAS_IOPORT

In a future patch HAS_IOPORT=n will disable inb()/outb() and friends at
compile time. With that choosing dynamically between I/O port and MMIO
access via GNERIC_IOMAP will not work. So only select GENERIC_IOMAP when
HAS_IOPORT is selected.
Co-developed-by: Arnd Bergmann <arnd@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@kernel.org>
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Link: https://lore.kernel.org/r/20240403122851.38808-2-schnelle@linux.ibm.comSigned-off-by: Geert Uytterhoeven <geert@linux-m68k.org>

arch/m68k/Kconfig

@@ -18,7 +18,7 @@ config M68K
 	select DMA_DIRECT_REMAP if M68K_NONCOHERENT_DMA && !COLDFIRE
 	select GENERIC_ATOMIC64
 	select GENERIC_CPU_DEVICES
-	select GENERIC_IOMAP
+	select GENERIC_IOMAP if HAS_IOPORT
 	select GENERIC_IRQ_SHOW
 	select GENERIC_LIB_ASHLDI3
 	select GENERIC_LIB_ASHRDI3