[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/Feature/varargs_new.ll b/llvm/test/Feature/varargs_new.ll
index a46f270..ca5599d 100644
--- a/llvm/test/Feature/varargs_new.ll
+++ b/llvm/test/Feature/varargs_new.ll
@@ -24,7 +24,7 @@
         %tmp = va_arg i8** %ap, i32             ; <i32> [#uses=1]
 
         ; Demonstrate usage of llvm.va_copy and llvm_va_end
-        %apv = load i8** %ap            ; <i8*> [#uses=1]
+        %apv = load i8*, i8** %ap            ; <i8*> [#uses=1]
         %va0.upgrd.2 = bitcast i8** %aq to i8*          ; <i8*> [#uses=1]
         %va1.upgrd.3 = bitcast i8* %apv to i8*          ; <i8*> [#uses=1]
         call void @llvm.va_copy( i8* %va0.upgrd.2, i8* %va1.upgrd.3 )