ogle/program/server: detect elf.EM_X86_64.

TBR=r
R=r
https://golang.org/cl/86370044
diff --git a/program/server/server.go b/program/server/server.go
index c9a425c..315ce2d 100644
--- a/program/server/server.go
+++ b/program/server/server.go
@@ -88,6 +88,8 @@
 			case elf.ELFCLASS64:
 				return &arch.AMD64, dwarfData, nil
 			}
+		case elf.EM_X86_64:
+			return &arch.AMD64, dwarfData, nil
 		}
 		return nil, nil, fmt.Errorf("unrecognized ELF architecture")
 	}