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/runtime/elf_file_impl.h b/runtime/elf_file_impl.h
index 3ad096f..0f466bd 100644
--- a/runtime/elf_file_impl.h
+++ b/runtime/elf_file_impl.h
@@ -119,12 +119,9 @@
   bool FixupProgramHeaders(Elf_Addr base_address);
   bool FixupSymbols(Elf_Addr base_address, bool dynamic);
   bool FixupRelocations(Elf_Addr base_address);
-  bool FixupDebugSections(typename std::make_signed<Elf_Off>::type base_address_delta);
-  bool ApplyOatPatchesTo(const char* target_section_name,
-                         typename std::make_signed<Elf_Off>::type base_address_delta);
-  static bool ApplyOatPatches(const uint8_t* patches, const uint8_t* patches_end,
-                              const char* target_section_name,
-                              typename std::make_signed<Elf_Off>::type delta,
+  bool FixupDebugSections(Elf_Addr base_address_delta);
+  bool ApplyOatPatchesTo(const char* target_section_name, Elf_Addr base_address_delta);
+  static void ApplyOatPatches(const uint8_t* patches, const uint8_t* patches_end, Elf_Addr delta,
                               uint8_t* to_patch, const uint8_t* to_patch_end);
 
   bool Strip(std::string* error_msg);