Fixes the following W=1 kernel build warning(s):

 drivers/bus/fsl-mc/fsl-mc-bus.c:30: warning: expecting prototype for Default DMA mask for devices on a fsl(). Prototype was for FSL_MC_DEFAULT_DMA_MASK() instead
 drivers/bus/fsl-mc/fsl-mc-bus.c:45: warning: Function parameter or member 'fsl_mc_regs' not described in 'fsl_mc'
 drivers/bus/fsl-mc/fsl-mc-bus.c:124: warning: Function parameter or member 'dev' not described in 'fsl_mc_bus_uevent'
 drivers/bus/fsl-mc/fsl-mc-bus.c:124: warning: Function parameter or member 'env' not described in 'fsl_mc_bus_uevent'
 drivers/bus/fsl-mc/fsl-mc-bus.c:480: warning: Function parameter or member 'mc_driver' not described in '__fsl_mc_driver_register'
 drivers/bus/fsl-mc/fsl-mc-bus.c:480: warning: Function parameter or member 'owner' not described in '__fsl_mc_driver_register'
 drivers/bus/fsl-mc/fsl-mc-bus.c:511: warning: Function parameter or member 'mc_driver' not described in 'fsl_mc_driver_unregister'
 drivers/bus/fsl-mc/fsl-mc-bus.c:571: warning: Function parameter or member 'dev' not described in 'fsl_mc_get_root_dprc'
 drivers/bus/fsl-mc/fsl-mc-bus.c:571: warning: Function parameter or member 'root_dprc_dev' not described in 'fsl_mc_get_root_dprc'
 drivers/bus/fsl-mc/fsl-mc-bus.c:739: warning: Function parameter or member 'dev' not described in 'fsl_mc_is_root_dprc'
 drivers/bus/fsl-mc/fsl-mc-bus.c:767: warning: Function parameter or member 'obj_desc' not described in 'fsl_mc_device_add'
 drivers/bus/fsl-mc/fsl-mc-bus.c:767: warning: Function parameter or member 'mc_io' not described in 'fsl_mc_device_add'
 drivers/bus/fsl-mc/fsl-mc-bus.c:767: warning: Function parameter or member 'parent_dev' not described in 'fsl_mc_device_add'
 drivers/bus/fsl-mc/fsl-mc-bus.c:767: warning: Function parameter or member 'new_mc_dev' not described in 'fsl_mc_device_add'
 drivers/bus/fsl-mc/fsl-mc-bus.c:767: warning: expecting prototype for Add a newly discovered fsl(). Prototype was for fsl_mc_device_add() instead
 drivers/bus/fsl-mc/fsl-mc-bus.c:1066: warning: Function parameter or member 'pdev' not described in 'fsl_mc_bus_probe'
 drivers/bus/fsl-mc/fsl-mc-bus.c:1190: warning: Function parameter or member 'pdev' not described in 'fsl_mc_bus_remove'

Cc: Stuart Yoder <stuyoder@gmail.com>
Cc: German Rivera <German.Rivera@freescale.com>
Reviewed-by: Laurentiu Tudor <laurentiu.tudor@nxp.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20210617110500.15907-3-lee.jones@linaro.orgSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>