libc: simplify ssse3 detection

Since ssse3 is required as part of Android's ABI, even for 32-bit x86
(https://developer.android.com/ndk/guides/abis#sa), we can simplify
these ifuncs away.

Bug: 358360849
Test: mma
Change-Id: Ife68c7f492cc1b179aa332c12ab35b2ad6b9795a
diff --git a/libc/arch-x86/string/ssse3-strncmp-atom.S b/libc/arch-x86/string/ssse3-strncmp-atom.S
index 2bf5002..234f728 100644
--- a/libc/arch-x86/string/ssse3-strncmp-atom.S
+++ b/libc/arch-x86/string/ssse3-strncmp-atom.S
@@ -30,6 +30,5 @@
 
 
 #define USE_AS_STRNCMP
-#define STRCMP  strncmp_ssse3
+#define STRCMP  strncmp
 #include "ssse3-strcmp-atom.S"
-