HID: amd_sfh: Set the AMD SFH driver to depend on x86

Considering that amd_sfh exists only on AMD platforms, set the AMD SFH
driver to depend on x86 to avoid build warnings or errors on other
architectures, as shown below.

drivers/hid/amd-sfh-hid/amd_sfh_pcie.c: In function 'amd_mp2_pci_probe':
drivers/hid/amd-sfh-hid/amd_sfh_pcie.c:413:21: error: 'boot_cpu_data'
undeclared (first use in this function); did you mean 'boot_cpu_hwid'?
  413 |                 if (boot_cpu_data.x86 >= 0x1A)
      |                     ^~~~~~~~~~~~~
      |                     boot_cpu_hwid

Fixes: 6296562f ("HID: amd_sfh: Extend MP2 register access to SFH")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Closes: https://lore.kernel.org/all/20240228145648.41c493ec@canb.auug.org.au/


Signed-off-by: Basavaraj Natikar <Basavaraj.Natikar@amd.com>
Signed-off-by: Jiri Kosina <jkosina@suse.com>