change default location of calibration file in drc configuration file

calibration/src/drc/minimal.drc

@@ -29,7 +29,7 @@ MCInterpolationType = H
 MCMultExponent = 3
 MCFilterLen = 65535
 MCNumPoints = 0
-MCPointsFile = flat.txt
+MCPointsFile = drc/flat.txt
 MCMagType = D
 # MCFilterFile = rmcf.pcm
 MCFilterFileType = F