Building with the attached random configuration file,
drivers/built-in.o: In function `sc16is7xx_i2c_probe':
sc16is7xx.c:(.text+0x96379): undefined reference to `devm_regmap_init_i2c'
drivers/built-in.o: In function `sc16is7xx_init':
sc16is7xx.c:(.init.text+0x5147): undefined reference to `i2c_register_driver'
drivers/built-in.o: In function `sc16is7xx_exit':
sc16is7xx.c:(.exit.text+0x9af): undefined reference to `i2c_del_driver'