Rename parallelFor -> parallelForEachN.

So that it is clear that the function is a wrapper for for_each_n.

llvm-svn: 302718
diff --git a/lld/ELF/OutputSections.cpp b/lld/ELF/OutputSections.cpp
index b25aa06..c5db018 100644
--- a/lld/ELF/OutputSections.cpp
+++ b/lld/ELF/OutputSections.cpp
@@ -297,7 +297,7 @@
   if (Filler)
     fill(Buf, Sections.empty() ? Size : Sections[0]->OutSecOff, Filler);
 
-  parallelFor(0, Sections.size(), [=](size_t I) {
+  parallelForEachN(0, Sections.size(), [=](size_t I) {
     InputSection *Sec = Sections[I];
     Sec->writeTo<ELFT>(Buf);