arch/Config.in.x86: add MMX instruction set capability for Geode CPU

Currently, there is no MMX support for modern GEODE processors in Buildroot.
Yet, some packages like ffmpeg can leverage it when the package is built.

Signed-off-by: Cherniaev Andrei <dungeonlords789@naver.com>
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>

arch/Config.in.x86

@@ -521,11 +521,22 @@ config BR2_x86_steamroller
 	select BR2_X86_CPU_HAS_SSE4
 	select BR2_X86_CPU_HAS_SSE42
 config BR2_x86_geode
-	bool "geode"
-	# Don't include MMX support because there several variant of geode
-	# processor, some with MMX support, some without.
-	# See: http://en.wikipedia.org/wiki/Geode_%28processor%29
+	bool "geode (no mmx)"
 	depends on !BR2_x86_64
+	help
+	  For several variant of geode which have not MMX support.
+	  See https://en.wikipedia.org/wiki/Geode_%28processor%29 to
+	  determine if your particular Geode processor supports MMX or
+	  not.
+config BR2_x86_geode_mmx
+	bool "geode (with mmx)"
+	depends on !BR2_x86_64
+	select BR2_X86_CPU_HAS_MMX
+	help
+	  For several variant of geode which have MMX support.
+	  See https://en.wikipedia.org/wiki/Geode_%28processor%29 to
+	  determine if your particular Geode processor supports MMX or
+	  not.
 config BR2_x86_c3
 	bool "Via/Cyrix C3 (Samuel/Ezra cores)"
 	depends on !BR2_x86_64