default or selected kernelversion does not have config value CONFIG_OMAP_IOVMM.
Result is shown for kernelversion 6.5.1

OMAP IO Virtual Memory Manager Support

modulename: omap-iovmm.ko

configname: CONFIG_OMAP_IOVMM

Linux Kernel Configuration
└─>Device Drivers
└─>IOMMU Hardware Support
└─>OMAP IO Virtual Memory Manager Support
In linux kernel since version 3.1 (release Date: 2011-10-24)  
source code:
drivers/iommu/omap-iovmm.c

is selected by
CONFIG_VIDEO_OMAP3