make private function getLine static

- make private function getLine static to prevent clashing with
  same function from sanei_magic.c under cygwin static build

backend/canon_dr.c

@@ -7261,7 +7261,7 @@ getTransitionsX (struct scanner *s, int side, int left)
 /* Loop thru a getTransitions array, and use a simplified Hough transform
  * to divide likely edges into a 2-d array of bins. Then weight each
  * bin based on its angle and offset. Return the 'best' bin. */
-SANE_Status
+static SANE_Status
 getLine (int height, int width, int * buff,
  int slopes, double minSlope, double maxSlope,
  int offsets, int minOffset, int maxOffset,

backend/canon_dr.h

@@ -560,7 +560,7 @@ SANE_Status getEdgeSlope (int width, int height, int * top, int * bot,
 SANE_Status rotateOnCenter (struct scanner *s, int side,
   int centerX, int centerY, double slope);
 
-SANE_Status getLine (int height, int width, int * buff,
+static SANE_Status getLine (int height, int width, int * buff,
  int slopes, double minSlope, double maxSlope,
  int offsets, int minOffset, int maxOffset,
  double * finSlope, int * finOffset, int * finDensity);