dt-bindings: qcom: update maintainers (drop Akash and Mukesh)

Emails to Akash Asthana and Mukesh Savaliya bounce (550: Recipient
address rejected: User unknown in virtual alias table), so switch
maintainer to Bjorn (as active Qualcomm platform maintainer).

Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Acked-by: Rob Herring <robh@kernel.org>
Acked-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20220405063724.12850-1-krzysztof.kozlowski@linaro.org