Documentation: devres: add missing SPI helpers

A few SPI devm_* helpers were missing from the devres documentation.
This patch adds them.

Signed-off-by: David Lechner <dlechner@baylibre.com>
Link: https://patch.msgid.link/20240621-devm_spi_optimize_message-v1-1-3f9dcba6e95e@baylibre.com
Signed-off-by: Mark Brown <broonie@kernel.org>

Author: dlech

Documentation/driver-api/driver-model/devres.rst

@@ -465,6 +465,8 @@ SPI
   devm_spi_alloc_master()
   devm_spi_alloc_slave()
   devm_spi_register_controller()
+  devm_spi_register_host()
+  devm_spi_register_target()
 
 WATCHDOG
   devm_watchdog_register_device()