ANDROID: Add symbols for IIO SCMI module

Enabling this module adds two loadable kernel modules: "kfifo_buf.ko"
and "scmi_iio.ko".

Updates to android/abi_gki_aarch64.stg include:

11 function symbol(s) added
  'int __kfifo_from_user(struct __kfifo*, const void*, unsigned long, unsigned int*)'
  'int __kfifo_to_user(struct __kfifo*, void*, unsigned long, unsigned int*)'
  'void iio_buffer_init(struct iio_buffer*)'
  'void iio_buffer_put(struct iio_buffer*)'
  'int iio_device_attach_buffer(struct iio_dev*, struct iio_buffer*)'
  'int iio_device_claim_direct_mode(struct iio_dev*)'
  'void iio_device_release_direct_mode(struct iio_dev*)'
  'int iio_push_to_buffers(struct iio_dev*, const void*)'
  'u64 int_pow(u64, unsigned int)'
  'int scmi_driver_register(struct scmi_driver*, struct module*, const char*)'
  'void scmi_driver_unregister(struct scmi_driver*)'

"kfifo_buf.ko" adds the following symbols to
android/abi_gki_aarch64_virtual_device:

iio_buffer_init
iio_buffer_put
iio_device_attach_buffer
__kfifo_alloc
__kfifo_free
__kfifo_from_user
__kfifo_in
__kfifo_out
__kfifo_to_user

"scmi_iio.ko" adds the following symbols to
android/abi_gki_aarch64_virtual_device:

devm_iio_device_alloc
__devm_iio_device_register
iio_device_claim_direct_mode
iio_device_release_direct_mode
iio_push_to_buffers
int_pow
scmi_driver_register
scmi_driver_unregister
strrchr

Bug: 315309338
Change-Id: If55d0bd8be0955a4bbf0a5ca091b23053a0c3963
Signed-off-by: Brian Daniels <briandaniels@google.com>