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-wcscat-atom.S b/libc/arch-x86/string/ssse3-wcscat-atom.S
index a307983..8a389a3 100644
--- a/libc/arch-x86/string/ssse3-wcscat-atom.S
+++ b/libc/arch-x86/string/ssse3-wcscat-atom.S
@@ -85,7 +85,7 @@
 #define USE_AS_WCSCAT
 
 .text
-ENTRY (wcscat_ssse3)
+ENTRY (wcscat)
 	PUSH    (%edi)
 	mov	STR1(%esp), %edi
 	mov	%edi, %edx
@@ -111,4 +111,4 @@
 #define RETURN  POP(%edi);	ret;	CFI_PUSH(%edi)
 #include "ssse3-wcscpy-atom.S"
 
-END (wcscat_ssse3)
+END (wcscat)