Split .oat_patches to multiple sections.

.oat_patches section currently contains encoded patch locations for
several other sections. Split it to several sections - one for each
of the destination sections. For example, .text.oat_patches section
contains patch locations for the .text section.

This ensures that if we strip some the sections using standard
tools, we strip the corresponding .oat_patches section as well.

It also makes the overall design simpler.
I should have done it this way in the first place.

Since ApplyOatPatches has been simplified and uses unaligned memory
access, this also fixes bug 21403573.

Bug:20556771
Bug:21403573
Change-Id: Iae7c423911507b524eec500e8d61744046fcd3ba
diff --git a/compiler/elf_writer_quick.h b/compiler/elf_writer_quick.h
index 955b568..fd202ee 100644
--- a/compiler/elf_writer_quick.h
+++ b/compiler/elf_writer_quick.h
@@ -35,7 +35,7 @@
                      const CompilerDriver& driver)
       SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
-  static void EncodeOatPatches(const OatWriter::PatchLocationsMap& sections,
+  static void EncodeOatPatches(const std::vector<uintptr_t>& locations,
                                std::vector<uint8_t>* buffer);
 
  protected: