As reported in STAR 9001165532, an SLC control reg read (for checking
busy state) right after SLC invalidate command may incorrectly return
NOT busy causing software to NOT spin-wait while operation is underway.
(and for some reason this only happens if L1 cache is also disabled - as
required by IOC programming model)

Suggested workaround is to do an additional Control Reg read, which
ensures the 2nd read gets the right status.

Cc: stable@vger.kernel.org  #4.10
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
[vgupta: reworte changelog a bit]
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>