thermal: int340x: Limit Kconfig to 64-bit

32-bit processors cannot generally access 64-bit MMIO registers
atomically, and it is unknown in which order the two halves of
this registers would need to be read:

drivers/thermal/intel/int340x_thermal/processor_thermal_mbox.c: In function 'send_mbox_cmd':
drivers/thermal/intel/int340x_thermal/processor_thermal_mbox.c:79:37: error: implicit declaration of function 'readq'; did you mean 'readl'? [-Werror=implicit-function-declaration]
   79 |                         *cmd_resp = readq((void __iomem *) (proc_priv->mmio_base + MBOX_OFFSET_DATA));
      |                                     ^~~~~
      |                                     readl

The driver already does not build for anything other than x86,
so limit it further to x86-64.

Fixes: aeb58c8 ("thermal/drivers/int340x: processor_thermal: Suppot 64 bit RFIM responses")
Signed-off-by: Arnd Bergmann <[email protected]>
Reviewed-by: Srinivas Pandruvada <[email protected]>
Reviewed-by: Randy Dunlap <[email protected]>
Signed-off-by: Rafael J. Wysocki <[email protected]>

drivers/thermal/intel/int340x_thermal/Kconfig

@@ -5,12 +5,12 @@
 
 config INT340X_THERMAL
 	tristate "ACPI INT340X thermal drivers"
-	depends on X86 && ACPI && PCI
+	depends on X86_64 && ACPI && PCI
 	select THERMAL_GOV_USER_SPACE
 	select ACPI_THERMAL_REL
 	select ACPI_FAN
 	select INTEL_SOC_DTS_IOSF_CORE
-	select PROC_THERMAL_MMIO_RAPL if X86_64 && POWERCAP
+	select PROC_THERMAL_MMIO_RAPL if POWERCAP
 	help
 	  Newer laptops and tablets that use ACPI may have thermal sensors and
 	  other devices with thermal control capabilities outside the core