sdemmc: update fix adj tuning method

sdemmc: update fix adj tuning method

PD#172367: sdemmc: update fix adj tuning method

All adj delay are avalible is not fair when
fix adj mode were used for tuning.
We had tried to add all data with rx delay
to find out the unstable adj delay point.
This method can not cover all scene.
For example:
All adj delay are available as below.
ADJ   0   1   2   3   4   0   1
Src   --__--__--__--__--__--__--
D0    __________________--------
D1    __________________--------
D2    __________________--------
D3    __________________--------
when same rx delay were added to all data line.
All adj delay are still avalible as below.
ADJ   0   1   2   3   4   0   1
Src   --__--__--__--__--__--__--
D0    ----__________________----
D1    ----__________________----
D2    ----__________________----
D3    ----__________________----

So, a new method to find out the unstable adj point
were designed for better compatibility.
Rx delay were added on only 1 data line, such as D1.

When rx delay were added on D1 only. Adj delay 1 is
not available anymore as below.
ADJ   0   1   2   3   4   0   1
Src   --__--__--__--__--__--__--
D0    __________________--------
D1    ----__________________----
D2    __________________--------
D3    __________________--------

In this way, the unsatble adj delay could be
distinguished.

Change-Id: I0488dec001a55f6b50b431ee4d691c872947f0f3
Signed-off-by: Yonghui Yu <yonghui.yu@amlogic.com>