soc/amd/cpu: smbios: Set external clock to 100 MHz

Set external clock to 100MHz.

source: PPR #57254

Change-Id: I99f73695019612d58b0c78c6985370d23c78b729
Signed-off-by: Naresh Solanki <naresh.solanki@9elements.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/85636
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Maximilian Brune <maximilian.brune@9elements.com>

src/soc/amd/glinda/cpu.c

@@ -7,11 +7,16 @@
 #include <cpu/amd/microcode.h>
 #include <cpu/cpu.h>
 #include <device/device.h>
+#include <smbios.h>
 #include <soc/cpu.h>
 
 _Static_assert(CONFIG_MAX_CPUS == 24, "Do not override MAX_CPUS. To reduce the number of "
 	"available cores, use the downcore_mode and disable_smt devicetree settings instead.");
 
+unsigned int smbios_processor_external_clock(void)
+{
+	return 100; // 100 MHz
+}
 static void zen_2_3_init(struct device *dev)
 {
 	check_mca();