Always log the value when an alignment check fails.

And move checking that the alignment is a power of two to compile-time.

Change-Id: I551f364af05912958ed2d4d095b1ce35b6abaf6e
diff --git a/src/oat.cc b/src/oat.cc
index 8bf8299..14040f3 100644
--- a/src/oat.cc
+++ b/src/oat.cc
@@ -51,13 +51,13 @@
 
 uint32_t OatHeader::GetExecutableOffset() const {
   DCHECK(IsValid());
-  DCHECK(IsAligned(executable_offset_, kPageSize));
+  DCHECK_ALIGNED(executable_offset_, kPageSize);
   CHECK_GT(executable_offset_, sizeof(OatHeader));
   return executable_offset_;
 }
 
 void OatHeader::SetExecutableOffset(uint32_t executable_offset) {
-  DCHECK(IsAligned(executable_offset, kPageSize));
+  DCHECK_ALIGNED(executable_offset, kPageSize);
   CHECK_GT(executable_offset, sizeof(OatHeader));
   DCHECK(IsValid());
   DCHECK_EQ(executable_offset_, 0U);