ASoC: SOF: fix error in verbose ipc command parsing

Remove the erroneous addition of "SET_VALUE" to the GLB
IPC command string.

Signed-off-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>