soc/intel/xeon_sp: Refactor `get_threads_per_package()`

Reduce the visibility of the `get_threads_per_package()` function and
retype its return value to `unsigned int`.

Change-Id: Ie71730d9a89eb7c4bb82d09d140fbcec7a6fe5f3
Signed-off-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/58914
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Felix Held <felix-coreboot@felixheld.de>

src/soc/intel/xeon_sp/include/soc/util.h

@@ -9,7 +9,6 @@
 void unlock_pam_regions(void);
 uint8_t get_stack_busno(const uint8_t stack);
 msr_t read_msr_ppin(void);
-int get_threads_per_package(void);
 int get_platform_thread_count(void);
 const IIO_UDS *get_iio_uds(void);
 unsigned int soc_get_num_cpus(void);

src/soc/intel/xeon_sp/util.c

@@ -74,7 +74,7 @@ msr_t read_msr_ppin(void)
 	return ppin;
 }
 
-int get_threads_per_package(void)
+static unsigned int get_threads_per_package(void)
 {
 	unsigned int core_count, thread_count;
 	cpu_read_topology(&core_count, &thread_count);