Does that code even work? E.g. in sound/soc/msm/msm8x16.c
ioremap(LPASS_CSR_GP_IO_MUX_SPKR_CTL , 4);
The ioremap() is aligning the address on PAGE_MASK and the register may not be where you think. I haven't checked the details, but it seems strange.
In the 4.9 kernel there is no longer any reference to the 0x07702000 register. Instead the 0x07708000 is defined in the device tree. And that register is present in the HW register document: