cpu/intel/*/*_init: use mca_get_bank_count()

Use the common mca_get_bank_count function instead of open-coding the
functionality to get the MCA bank number. Also re-type the num_banks
variable from signed in to unsigned int, since the number of MCA bank is
always positive, and make it constant.

In the case of Intel model 2065x the mca_get_bank_count() call replaces
a magic number.

Change-Id: I245b15f57e77edca179e9e28965383a227617174
Signed-off-by: Felix Held <felix-coreboot@felixheld.de>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/56244
Reviewed-by: Raul Rangel <rrangel@chromium.org>
Reviewed-by: Patrick Rudolph <siro@das-labor.org>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/cpu/intel/haswell/haswell_init.c

@@ -520,10 +520,7 @@ static void configure_mca(void)
 {
 	msr_t msr;
 	int i;
-	int num_banks;
-
-	msr = rdmsr(IA32_MCG_CAP);
-	num_banks = msr.lo & 0xff;
+	const unsigned int num_banks = mca_get_bank_count();
 
 	/* Enable all error reporting */
 	msr.lo = msr.hi = ~0;

src/cpu/intel/model_2065x/model_2065x_init.c

@@ -77,10 +77,11 @@ static void configure_mca(void)
 {
 	msr_t msr;
 	int i;
+	const unsigned int num_banks = mca_get_bank_count();
 
 	msr.lo = msr.hi = 0;
 	/* This should only be done on a cold boot */
-	for (i = 0; i < 7; i++)
+	for (i = 0; i < num_banks; i++)
 		wrmsr(IA32_MC_STATUS(i), msr);
 }
 

src/cpu/intel/model_206ax/model_206ax_init.c

@@ -301,10 +301,7 @@ static void configure_mca(void)
 {
 	msr_t msr;
 	int i;
-	int num_banks;
-
-	msr = rdmsr(IA32_MCG_CAP);
-	num_banks = msr.lo & 0xff;
+	const unsigned int num_banks = mca_get_bank_count();
 
 	msr.lo = msr.hi = 0;
 	/* This should only be done on a cold boot */