[llvm][test] Fix REQUIRES in extractelement-insertpoint.ll

The target is called "x86" not "x86_64".

Author: DavidSpickett

llvm/test/Transforms/SLPVectorizer/extractelement-insertpoint.ll

@@ -1,5 +1,5 @@
 ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
-; RUN: %if x86_64-registered-target %{ opt -S -passes=slp-vectorizer -mtriple=x86_64-grtev4-linux-gnu -o - < %s | FileCheck %s %}
+; RUN: %if x86-registered-target %{ opt -S -passes=slp-vectorizer -mtriple=x86_64-grtev4-linux-gnu -o - < %s | FileCheck %s %}
 ; RUN: %if aarch64-registered-target %{ opt -S -passes=slp-vectorizer -mtriple=aarch64-unknown-linux-gnu -o - < %s | FileCheck %s %}
 
 define i32 @crash() {