fix: add CPU detection for Intel Emerald Rapids (Xeon Platinum 8575C)

Problem:
Intel Xeon Platinum 8575C (Emerald Rapids, model 207 = exmodel 12, model 15)
was incorrectly detected as PRESCOTT (Pentium 4 era) instead of SAPPHIRERAPIDS.

Root cause:
1. In get_corename() function, case 12 (exmodel 12) only handled model 6
   (Arrow Lake) but missed model 15 (Emerald Rapids)
2. Missing break statement caused fall-through to case 15 (family 15,
   which is Pentium 4), returning CORE_PRESCOTT incorrectly

Changes:
- cpuid_x86.c: Add case 15 (Emerald Rapids) to exmodel 12 switch and
  add missing break statement
- dynamic.c: Add case 12 with model 15 for runtime detection of
  Emerald Rapids processors

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: airborne12

cpuid_x86.c

@@ -2424,6 +2424,7 @@ int get_coretype(void){
 	}
       case 12:
 	switch (model) {
+	  case 15: // Emerald Rapids (e.g., Intel Xeon Platinum 8575C)
 	  case 6: // Arrow Lake
 	  if(support_amx_bf16())
 	    return CORE_SAPPHIRERAPIDS;
@@ -2438,6 +2439,7 @@ int get_coretype(void){
 	  else
 	    return CORE_NEHALEM;
 	}
+	break;
       }
     case 15:
       if (model <= 0x2) return CORE_NORTHWOOD;

driver/others/dynamic.c

@@ -792,7 +792,7 @@ static gotoblas_t *get_coretype(void){
 	  }
         }
         if (model == 7) {
-	  if (support_avx512()) 
+	  if (support_avx512())
 	    return &gotoblas_SKYLAKEX;
 	  if(support_avx2())
 	    return &gotoblas_HASWELL;
@@ -803,7 +803,27 @@ static gotoblas_t *get_coretype(void){
 	    openblas_warning(FALLBACK_VERBOSE, NEHALEM_FALLBACK);
 	    return &gotoblas_NEHALEM; //OS doesn't support AVX. Use old kernels.
 	  }
-        }      
+        }
+	return NULL;
+      case 12:
+        // Emerald Rapids (e.g., Intel Xeon Platinum 8575C, model 207 = exmodel 12, model 15)
+        if (model == 15) {
+	   if(support_amx_bf16())
+	     return &gotoblas_SAPPHIRERAPIDS;
+	   if(support_avx512_bf16())
+             return &gotoblas_COOPERLAKE;
+          if (support_avx512())
+	    return &gotoblas_SKYLAKEX;
+	  if(support_avx2())
+	    return &gotoblas_HASWELL;
+	  if(support_avx()) {
+	    openblas_warning(FALLBACK_VERBOSE, SANDYBRIDGE_FALLBACK);
+	    return &gotoblas_SANDYBRIDGE;
+	  } else {
+	    openblas_warning(FALLBACK_VERBOSE, NEHALEM_FALLBACK);
+	    return &gotoblas_NEHALEM;
+	  }
+        }
 	return NULL;
       }
       break;