scan four bits for idcdcP/N for AMACstar when tuning input current monitoring

The CUR10V calibration registers (idcdcP/N) for AMACstar has 4 bits (vs 3 bits for AMACv2). And we have been only scanning the first 3 bits so far, which sometimes fail to find the optimal idcdcP/N for some AMAC. This MR tries to fix this by scaning four bits for AMACstar and three bits for AMACv2.

One caveat of the increased scan is the increased time (4 times more time) needed for the scan. Estimate of basic test is now 6 min per board (vs. 2min45s per board before this change), and the advanced test is now 1h8min per board (vs. 23min per board before this change). Therefore, we optimized the tuning process in the basic test to only scan idcdcP or only scan idcdcN; and in the advanced test we skip odd number of idcdcP/N. After this change, the new time is now similar to the time before this MR.

To avoid conflicts, merge this MR first: !142 (merged)