soc/intel/common/block/cpu: Fix cpu_get_power_max

To avoid rounding errors with the current data types, the formula in
this function must be converted.

Change-Id: I75d05165fd9e5a0992330df00f8665a05d2daeb3
Signed-off-by: Mario Scheithauer <mario.scheithauer@siemens.com>
Reviewed-on: https://review.coreboot.org/25584
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Patrick Georgi <pgeorgi@google.com>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>

src/soc/intel/common/block/cpu/cpulib.c

@@ -287,7 +287,7 @@ uint32_t cpu_get_power_max(void)
 	msr = rdmsr(MSR_PKG_POWER_SKU_UNIT);
 	power_unit = 2 << ((msr.lo & 0xf) - 1);
 	msr = rdmsr(MSR_PKG_POWER_SKU);
-	return ((msr.lo & 0x7fff) / power_unit) * 1000;
+	return (msr.lo & 0x7fff) * 1000 / power_unit;
 }
 
 uint32_t cpu_get_max_turbo_ratio(void)