warning: #191-D: type qualifier is meaningless on cast type

typedef union _ldopctl_t_
{
    INT32U Word;
    struct
    {
        INT32U vadj         : 6;
        INT32U reserved     : 26;
    }Bits;
}LDO_Ctrl_struct, *pLDO_Ctrl_struct;

#define LDO_250V                  0x00

#define reg(x, y)       (*((volatile x)(y)))

#define SYSCTL_LDOPCTL          0x400fe034  /* LDO power control register        */

#define RegSysCtl_LDOPCTL       (reg(pLDO_Ctrl_struct, SYSCTL_LDOPCTL   ))

RegSysCtl_LDOPCTL.Bits.vadj = LDO_250V;