CONFIG_SOC_IMX7ULP is not available for thedefaultarchitecture x86.
Result is shown for architecture arm

i.MX7ULP support

modulename: cpuidle-imx7ulp.ko

and/or

mach-imx7ulp.ko

configname: CONFIG_SOC_IMX7ULP

Linux Kernel Configuration
└─>Freescale i.MX family
└─>i.MX7ULP support
In linux kernel since version 4.14.326 (release Date: 2023-09-23)  
This enables support for Freescale i.MX7 Ultra Low Power processor.

source code:
/arch/arm/mach-imx/cpuidle-imx7ulp.c


is selected by
CONFIG_PINCTRL_IMX7ULP