Add p9n 2.3 to p9_frequency_buckets.H

Change-Id: I06f679f555c5dfd0a66f5b9bc5ff1e3424c4aae7
Reviewed-on: http://ralgit01.raleigh.ibm.com/gerrit1/55383
Tested-by: FSP CI Jenkins <fsp-CI-jenkins+hostboot@us.ibm.com>
Tested-by: Jenkins Server <pfd-jenkins+hostboot@us.ibm.com>
Tested-by: HWSV CI <hwsv-ci+hostboot@us.ibm.com>
Tested-by: PPE CI <ppe-ci+hostboot@us.ibm.com>
Tested-by: Hostboot CI <hostboot-ci+hostboot@us.ibm.com>
Reviewed-by: Soma Bhanutej <soma.bhanu@in.ibm.com>
Reviewed-by: Matt K. Light <mklight@us.ibm.com>
Dev-Ready: Matt K. Light <mklight@us.ibm.com>
Reviewed-by: Jennifer A. Stofer <stofer@us.ibm.com>
Reviewed-on: http://ralgit01.raleigh.ibm.com/gerrit1/55392
Tested-by: Jenkins OP Build CI <op-jenkins+hostboot@us.ibm.com>
Tested-by: Jenkins OP HW <op-hw-jenkins+hostboot@us.ibm.com>
Reviewed-by: Daniel M. Crowell <dcrowell@us.ibm.com>

src/import/chips/p9/common/include/p9_frequency_buckets.H

@@ -99,6 +99,13 @@ const uint32_t OBUS_PLL_FREQ_LIST_P9N_22[OBUS_PLL_FREQ_BUCKETS] =
     1563
 };
 
+const uint32_t OBUS_PLL_FREQ_LIST_P9N_23[OBUS_PLL_FREQ_BUCKETS] =
+{
+    1611,
+    1250,
+    1563
+};
+
 const uint32_t OBUS_PLL_FREQ_LIST_P9C_10[OBUS_PLL_FREQ_BUCKETS] =
 {
     1601,