platform/x86/amd/hsmp: Check HSMP support on AMD family of processors

HSMP interface is supported only on few x86 processors from AMD.
Accessing HSMP registers on rest of the platforms might cause
unexpected behaviour. So add a check.

Also unavailability of this interface on rest of the processors
is not an error. Hence, use pr_info() instead of the pr_err() to
log the message.

Signed-off-by: Suma Hegde <suma.hegde@amd.com>
Reviewed-by: Naveen Krishna Chatradhi <naveenkrishna.chatradhi@amd.com>
Link: https://lore.kernel.org/r/20240603081512.142909-1-suma.hegde@amd.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>