[openrisc] OR16 more insns

[jimmy87@sunplus.com.tw]

{ "h.xori",    "r15,M",      "0xE 0x7  MMMM MMMM"},
{ "h.ori",     "r15,M",      "0xE 0x8  MMMM MMMM"},
{ "h.andi",    "r15,M",      "0xE 0x9  MMMM MMMM"},
{ "h.addis",   "r15,M",      "0xE 0xA  MMMM MMMM"},
{ "h.addiu",   "r15,M",      "0xE 0xB  MMMM MMMM"},
I want to drive OR16 to the extreme, so
I want to pose the above three registers. I don't know if it's good or not.
the default source and target registers are r15.
Best regards, Jimmy