dt-bindings: pinctrl: qcom,ipq6018: correct BLSP6->BLSP0 functions

dt-bindings: pinctrl: qcom,ipq6018: correct BLSP6->BLSP0 functions

The pin controller driver has BLSP functions from 0 to 5, not 1 to 6.
Add missing blsp0_i2c, blsp0_spi (already used in ipq6018-cp01-c1) and
blsp0_uart.  Drop blsp6_i2c and blsp6_spi.

This fixes dtbs_check warning:

  ipq6018-cp01-c1.dtb: pinctrl@1000000: spi-0-state: 'oneOf' conditional failed, one must be fixed:
    'bias-pull-down', 'drive-strength', 'function', 'pins' do not match any of the regexes: '-pins$', 'pinctrl-[0-9]+'
    'blsp0_spi' is not one of ['adsp_ext', 'alsp_int', .....

Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20221016170035.35014-10-krzysztof.kozlowski@linaro.org
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>