[opaque pointer type] Add textual IR support for explicit type parameter to load instruction

Essentially the same as the GEP change in r230786.

A similar migration script can be used to update test cases, though a few more
test case improvements/changes were required this time around: (r229269-r229278)

import fileinput
import sys
import re

pat = re.compile(r"((?:=|:|^)\s*load (?:atomic )?(?:volatile )?(.*?))(| addrspace\(\d+\) *)\*($| *(?:%|@|null|undef|blockaddress|getelementptr|addrspacecast|bitcast|inttoptr|\[\[[a-zA-Z]|\{\{).*$)")

for line in sys.stdin:
  sys.stdout.write(re.sub(pat, r"\1, \2\3*\4", line))

Reviewers: rafael, dexonsmith, grosser

Differential Revision: http://reviews.llvm.org/D7649

llvm-svn: 230794
diff --git a/llvm/test/CodeGen/MSP430/memset.ll b/llvm/test/CodeGen/MSP430/memset.ll
index bf10544..76cfb29 100644
--- a/llvm/test/CodeGen/MSP430/memset.ll
+++ b/llvm/test/CodeGen/MSP430/memset.ll
@@ -8,7 +8,7 @@
 define void @test() nounwind {
 entry:
 ; CHECK-LABEL: test:
-  %0 = load i8** @buf, align 2
+  %0 = load i8*, i8** @buf, align 2
 ; CHECK: mov.w &buf, r15
 ; CHECK-NEXT: mov.w #5, r14
 ; CHECK-NEXT: mov.w #128, r13