Remove dependency on SSE4 instructions, reverting back to "core2" as …

…a target CPU architecture for x86_64.

Resolves https://bugs.launchpad.net/lxml/+bug/2059910

Makefile

@@ -65,7 +65,7 @@ wheel_%: dist/lxml-$(LXMLVERSION).tar.gz
 		-e AR=gcc-ar \
 		-e NM=gcc-nm \
 		-e RANLIB=gcc-ranlib \
-		-e CFLAGS="$(MANYLINUX_CFLAGS) $(if $(patsubst %aarch64,,$@),-march=core2 -msse4.1 -msse4.2,-march=armv8-a -mtune=cortex-a72)" \
+		-e CFLAGS="$(MANYLINUX_CFLAGS) $(if $(patsubst %aarch64,,$@),-march=core2,-march=armv8-a -mtune=cortex-a72)" \
 		-e LDFLAGS="$(MANYLINUX_LDFLAGS)" \
 		-e STATIC_DEPS="${STATIC_DEPS}" \
 		-e LIBXML2_VERSION="$(MANYLINUX_LIBXML2_VERSION)" \

pyproject.toml

@@ -51,7 +51,7 @@ environment.CFLAGS = "-O3 -g1 -pipe -fPIC -flto -march=core2 -mtune=generic"
 [[tool.cibuildwheel.overrides]]
 select = "*linux_x86_64"
 inherit.environment = "append"
-environment.CFLAGS = "-O3 -g1 -pipe -fPIC -flto -march=core2 -msse4.1 -msse4.2 -mtune=generic"
+environment.CFLAGS = "-O3 -g1 -pipe -fPIC -flto -march=core2 -mtune=generic"
 
 [[tool.cibuildwheel.overrides]]
 select = "*aarch64"
@@ -67,3 +67,4 @@ archs = ["AMD64", "x86"]
 # so additional arm64 wheels would suffice.  However, since the library build uses a mixed
 # amd64/arm64 setup, we build universal2 wheels regardless.
 archs = ["x86_64", "universal2"]
+M