We hereby declare the amd64 backend no longer experimental.
It compiles the vast majority of OpenBSD C code just fine.

Index: ir/be/amd64/amd64_bearch.c
--- ir/be/amd64/amd64_bearch.c.orig
+++ ir/be/amd64/amd64_bearch.c
@@ -777,7 +777,6 @@ static void amd64_init(void)
 	amd64_cconv_init();
 	x86_set_be_asm_constraint_support(&amd64_asm_constraints);
 
-	ir_target.experimental = "the amd64 backend is experimental and unfinished (consider the ia32 backend)";
 	ir_target.fast_unaligned_memaccess = true;
 	ir_target.float_int_overflow       = ir_overflow_indefinite;
 }
