dt-bindings: memory: snps,dw-umctl2-ddrc: Use more descriptive device name

The DT-schema name and the corresponding generic compatible string look
inappropriate in the current DW uMCTL2 DDRC DT-bindings:
1. DT-schema name contains undefined vendor-prefix. It's supposed to be
"snps", not "synopsys".
2. DT-schema name has "ecc" suffix. That is a device property, and has
nothing to do with the controller actual name.
3. The controller name is different. It's DW uMCTL2 DDRC. Just DDRC
doesn't identify the IP-core in subject.
4. There is no much point in using the IP-core version in the device name
since it can be retrieved from the corresponding device CSR. Moreover the
DW uMCTL2 DDRC driver doesn't differentiate the IP-core version at the
current state.

In order to fix all the inconsistencies described above we suggest to
rename the DT-schema to "snps,dw-umctl2-ddrc.yaml", deprecate the
compatible string "snps,ddrc-3.80a" and define a new generic device
name as "snps,dw-umctl2-ddrc".

Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20220910194237.10142-16-Sergey.Semin@baikalelectronics.ru