Audio: SRC: Tune: Add pkg load signal for Octave

The added check loads for Octave the signal package. In
Matlab it is available if licensed without need for explicitly
loading it.

Signed-off-by: Seppo Ingalsuo <seppo.ingalsuo@linux.intel.com>

Author: singalsu

src/audio/src/tune/sof_src_generate.m

@@ -49,6 +49,11 @@
 	error('Sample rates in/out matrix size mismatch!');
 end
 
+if exist('OCTAVE_VERSION', 'builtin')
+  pkg load signal
+end
+
+
 %% Exported coefficients type int16, int24, int32, float
 
 switch cfg.ctype