The R_ARM_TARGET2 relocation is used in ARM exception tables to encode a data dependency that will only be dereferenced by code in the run-time support library. In a similar way to R_ARM_TARGET1 the handling of the relocation is target specific, it maps to one of R_ARM_ABS32, R_ARM_REL32 or R_ARM_GOT_PREL. The choice depends on the run-time library. R_ARM_GOT_PREL is used for linux and BSD, R_ARM_ABS32 and R_ARM_REL32 are used for bare-metal.
I've implemented R_ARM_TARGET2 in lld using the same command line option as GNU ld https://sourceware.org/binutils/docs/ld/ARM.html#ARM
The default is R_ARM_GOT_PREL as this is the default in Gold and the linux targeting BFD linkers.