misc/llama-cpp: Fix run-time on older CPUs

... by disabling explicit flags that enable them.

misc/llama-cpp/Makefile

@@ -1,7 +1,7 @@
 PORTNAME=	llama-cpp
 DISTVERSIONPREFIX=	b
 DISTVERSION=	5097
-PORTREVISION=	1
+PORTREVISION=	2
 CATEGORIES=	misc # machine-learning
 
 MAINTAINER=	yuri@FreeBSD.org
@@ -26,6 +26,7 @@ SHEBANG_GLOB=	*.py
 
 CMAKE_ON=	BUILD_SHARED_LIBS
 CMAKE_OFF=	GGML_NATIVE \
+		FREEBSD_ALLOW_ADVANCED_CPU_FEATURES \
 		LLAMA_BUILD_TESTS
 CMAKE_TESTING_ON=	LLAMA_BUILD_TESTS
 

misc/llama-cpp/files/patch-ggml_src_ggml-cpu_CMakeLists.txt

@@ -0,0 +1,11 @@
+--- ggml/src/ggml-cpu/CMakeLists.txt.orig	2025-04-10 23:26:06 UTC
++++ ggml/src/ggml-cpu/CMakeLists.txt
+@@ -236,7 +236,7 @@ function(ggml_add_cpu_backend_variant_impl tag_name)
+         else ()
+             if (GGML_NATIVE)
+                 list(APPEND ARCH_FLAGS -march=native)
+-            else ()
++            elseif (FREEBSD_ALLOW_ADVANCED_CPU_FEATURES)
+                 list(APPEND ARCH_FLAGS -msse4.2)
+                 list(APPEND ARCH_DEFINITIONS GGML_SSE42)
+                 if (GGML_F16C)