remoteproc: imx_dsp_rproc: Rename macro to reflect multiple contexts

remoteproc: imx_dsp_rproc: Rename macro to reflect multiple contexts

Rename WAIT_FW_READY to WAIT_FW_CONFIRMATION and FEATURE_DONT_WAIT_FW_READY
to FEATURE_SKIP_FW_CONFIRMATION. This way, the term CONFIRMATION covers:
- waiting for firmware to confirm it is ready to start;
- waiting for any other confirmation from firmware.

Signed-off-by: Iuliana Prodan <iuliana.prodan@nxp.com>
Reviewed-by: Frank Li <Frank.Li@nxp.com>
Reviewed-by: Daniel Baluta <daniel.baluta@nxp.com>
Link: https://lore.kernel.org/r/20251204122825.756106-2-iuliana.prodan@oss.nxp.com
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>