ipa: rkisp1: Use frame number passed to Algorithm::prepare()

Now that the Algorithm::prepare() function takes a frame number, we can
use it to replace the IPAActiveState::frameCount member.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>

src/ipa/rkisp1/ipa_context.cpp

@@ -192,15 +192,6 @@ namespace libcamera::ipa::rkisp1 {
  * \brief Analogue gain multiplier
  */
 
-/**
- * \var IPAActiveState::frameCount
- * \brief Counter of requests queued to the IPA module
- *
- * The counter is reset to 0 when the IPA module is configured, and is
- * incremented for each request being queued, after calling the
- * Algorithm::prepare() function of all algorithms.
- */
-
 /**
  * \struct IPAFrameContext
  * \brief Per-frame context for algorithms