cpu/x86/mp_init: move printing of failure message into mp_init_with_smm

Each CPU/SoC checks the return value of the mp_init_with_smm and prints
the same error message if it wasn't successful, so move this check and
printk to mp_init_with_smm. For this the original mp_init_with_smm
function gets renamed to do_mp_init_with_smm and a new mp_init_with_smm
function is created which then calls do_mp_init_with_smm, prints the
error if it didn't return CB_SUCCESS and passes the return value of
do_mp_init_with_smm to its caller.

Since no CPU/SoC code handles a mp_init_with_smm failure apart from
printing a message, also add a comment at the mp_init_with_smm call
sites that the code might want to handle a failure.

Signed-off-by: Felix Held <felix-coreboot@felixheld.de>
Change-Id: I181602723c204f3e43eb43302921adf7a88c81ed
Reviewed-on: https://review.coreboot.org/c/coreboot/+/58498
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Raul Rangel <rrangel@chromium.org>
diff --git a/src/mainboard/emulation/qemu-i440fx/northbridge.c b/src/mainboard/emulation/qemu-i440fx/northbridge.c
index b7630a1..d041b0c 100644
--- a/src/mainboard/emulation/qemu-i440fx/northbridge.c
+++ b/src/mainboard/emulation/qemu-i440fx/northbridge.c
@@ -251,8 +251,8 @@
 {
 	const struct mp_ops *ops = CONFIG(SMM_TSEG) ? &mp_ops_with_smm : &mp_ops_no_smm;
 
-	if (mp_init_with_smm(cpu_bus, ops) != CB_SUCCESS)
-		printk(BIOS_ERR, "MP initialization failure.\n");
+	/* TODO: Handle mp_init_with_smm failure? */
+	mp_init_with_smm(cpu_bus, ops);
 }
 
 static void cpu_bus_init(struct device *dev)