[Upstream port] Add JTAG functionality

[EvgeniiDidin]

In ARC port we are creating wrappers of generic jtag functions.
ARC Jtag support might be splitted the next way:

• Adding basic r/w of ir/dr
• Adding arc_jtag_transactions*
• Adding arc_jtag startup, shutdown, status, idcode
• Reading registers
• Writing registers

[EvgeniiDidin]

Commit according to "Adding basic r/w of ir/dr" is:
95f9220

[EvgeniiDidin]

Commit according to "Adding arc_jtag_transactions*":
07712d5

[EvgeniiDidin]

Commit according to "Adding arc_jtag startup, shutdown, status, idcode":
ce523b8

[EvgeniiDidin]

Commits according to reading/writing registers:
5242a17 68aae0f 0a33cce