Fix DCHECK() in ElfBuilder.

Test: testrunner.py --target --32 --jit --debugable
Bug: 110133331
Change-Id: Idc558f156b432278479c65418b3efb37174fdd1c
diff --git a/libelffile/elf/elf_builder.h b/libelffile/elf/elf_builder.h
index 10541ec..4dde150 100644
--- a/libelffile/elf/elf_builder.h
+++ b/libelffile/elf/elf_builder.h
@@ -849,7 +849,8 @@
         LOG(FATAL) << "Unknown instruction set " << isa;
       }
     }
-    DCHECK_EQ(GetIsaFromHeader(elf_header), isa);
+    DCHECK_EQ(GetIsaFromHeader(elf_header),
+              (isa == InstructionSet::kArm) ? InstructionSet::kThumb2 : isa);
 
     elf_header.e_ident[EI_MAG0]       = ELFMAG0;
     elf_header.e_ident[EI_MAG1]       = ELFMAG1;