aubinator: add a custom handler for immediate register load

aubinator: add a custom handler for immediate register load

Transforming this :

0x00c77084:  0x11000001:  MI_LOAD_REGISTER_IMM
0x00c77088:  0x0000b020 : Dword 1
    Register Offset: 0x0000b020
    0x00c7708c:  0x00880038 : Dword 2
    Data DWord: 8912952

Into this:

0x007880f0:  0x11000001:  MI_LOAD_REGISTER_IMM
0x007880f4:  0x0000b020 : Dword 1
    Register Offset: 0x0000b020
    0x007880f8:  0x00080040 : Dword 2
    Data DWord: 524352
register L3CNTLREG2 (0xb020) : 0x80040
    SLM Enable: 0
    URB Allocation: 32
    URB Low Bandwidth: 0
    RO Allocation: 32
    RO Low Bandwidth: 0
    DC Allocation: 0
    DC Low Bandwidth: 0

v2: Drop unused arguments (Sirisha)
    Print out register name

Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>