Check alignment along with range of mapped file fragments

Improve sanity-checks of elf-file by adding alignment check
of mapped sections and section headers.

Bug: http://b/30687964
Change-Id: I7f06ddaa56a13989ce7be847b3a73c352e32c008
diff --git a/linker/linker_phdr.h b/linker/linker_phdr.h
index 89ec094..d6276ed 100644
--- a/linker/linker_phdr.h
+++ b/linker/linker_phdr.h
@@ -65,7 +65,7 @@
   bool LoadSegments();
   bool FindPhdr();
   bool CheckPhdr(ElfW(Addr));
-  bool CheckFileRange(ElfW(Addr) offset, size_t size);
+  bool CheckFileRange(ElfW(Addr) offset, size_t size, size_t alignment);
 
   bool did_read_;
   bool did_load_;