Internal relocation (type: OFFST_IMM) with register variables in Assembler

Question

.section .init
.globl _start
_start:

@GPFSEL2
GPFSEL2_Address = 0x3F200008

GPFSEL2 .req r1

ldr r1, = GPFSEL2_Address

mov r12, #1
lsl r12, #12
@Set GPIO 24 as out