x86/cpu: Add Intel CPU model number for rugged Panther Lake

Derivative of Panther Lake with P-cores and low power E-cores intended
for use in harsh environments.

Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: https://patch.msgid.link/20260515180224.13818-1-tony.luck@intel.com

arch/x86/include/asm/intel-family.h

@@ -29,6 +29,7 @@
  *		_N,_P	- other mobile parts
  *		_H	- premium mobile parts
  *		_S	- other client parts
+ *		_R	- ruggedized for harsh environment
  *
  *		Historical OPTDIFFs:
  *
@@ -151,6 +152,7 @@
 #define INTEL_LUNARLAKE_M		IFM(6, 0xBD) /* Lion Cove / Skymont */
 
 #define INTEL_PANTHERLAKE_L		IFM(6, 0xCC) /* Cougar Cove / Darkmont */
+#define INTEL_PANTHERLAKE_R		IFM(6, 0xE5) /* Cougar Cove / Darkmont */
 
 #define INTEL_WILDCATLAKE_L		IFM(6, 0xD5)