jtag: simplify the calls to Jim_SetResultFormatted()

jtag: simplify the calls to Jim_SetResultFormatted()

The documentation of Jim_SetResultFormatted() reports that the jim
objects passed as arguments would be freed if have zero refcount.

Remove the useless Jim_IncrRefCount()/Jim_DecrRefCount().
Remove the dangerous Jim_FreeNewObj() that should trigger a double
free(). Not tested due to lack of aice adapter.

While there, rename some CamelCase symbol.

Change-Id: Ic56704c83d6391c38f6b0efa6566784d453bc0fb
Signed-off-by: Antonio Borneo <borneo.antonio@gmail.com>
Reviewed-on: http://openocd.zylin.com/6190
Tested-by: jenkins
Reviewed-by: Tomas Vanek <vanekt@fbl.cz>