[Vala] bug in vapi

[pancake <pancake youterm com>]

I noticed that property support is not affected by the cprefix
CCode attribute.

Here's an example:

        [Compact]
        [CCode (cname="struct r_asm_t", free_function="r_asm_free", cprefix="r_asm_")]
        public class State {
                public unowned string buf_asm;
                public unowned string buf_hex;
                public State();
                public bool arch { set; };
                public bool set_arch(Arch arch);
                public bool set_bits(int bits);
                public bool set_syntax(Syntax syntax);
                public bool set_pc(uint64 addr);
                public bool set_big_endian(bool big);
                public bool disasm(uint8 *buf, int length);
        }


If we call to set_arch(Asm.Arch.X86); the C code is:
  r_asm_set_arch(R_ASM_ARCH_X86);

but if we do it using the 'arch' property:

  arch = Asm.Arch.X86;

the code doesnt follows the cprefix directive and translates it to:

  r_asm_state_set_arch(R_ASM_ARCH_X86);

which is obviously wrong :)

PD: This code is from radare libr project (fmi: radare.org)

  --pancake