dt-bindings: arm: add TQMa93xxLA SOM

TQMa93xxLA is a SOM variant in the TQ-Systems GmbH TQMa93xx series using
NXP i.MX93 CPU on an LGA type board.
MBa93xxCA is a starterkit base board for TQMa93xxLA on an adapter board.

Signed-off-by: Markus Niebel <Markus.Niebel@ew.tq-group.com>
Signed-off-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>