iwlwifi: acpi: remove dummy definition of iwl_sar_set_profile()

This function is only called from acpi.c, which is only included in
the makefile if CONFIG_ACPI is set.  So it doesn't make sense to
declare a dummy version of it when CONFIG_ACPI is not defined.

Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Link: https://lore.kernel.org/r/iwlwifi.20200926002540.1833ae348c7f.I3271f9d2f7e484779a6319a1514cd0b7221fe326@changeid


Signed-off-by: Luca Coelho <luciano.coelho@intel.com>