wrlib: Marked args as unused for compiler

The two functions require an argument which is used when the libXpm is
used, which means having the same argument list for the builtin code to be
permutable.

This patch adds the appropriate stuff to avoid a false report from the
compiler.

Signed-off-by: Christophe CURIS <christophe.curis@free.fr>

wrlib/nxpm.c

@@ -80,6 +80,12 @@ RImage *RGetImageFromXPMData(RContext * context, char **data)
 	int bsize;
 	int w, h, ccount, csize;
 
+	/*
+	 * When using libXpm we need the context argument but the code here does
+	 * not, so tell the compiler to not warn about it
+	 */
+	(void) context;
+
 	if (sscanf(data[line++], "%i %i %i %i", &w, &h, &ccount, &csize) != 4
 	    || w <= 0 || h <= 0 || ccount <= 0 || csize <= 0)
 		goto bad_format;
@@ -242,6 +248,12 @@ RImage *RLoadXPM(RContext * context, const char *file)
 	int w, h, ccount, csize;
 	FILE *f;
 
+	/*
+	 * When using libXpm we need the context argument but the code here does
+	 * not, so tell the compiler to not warn about it
+	 */
+	(void) context;
+
 	f = fopen(file, "rb");
 	if (!f) {
 		RErrorCode = RERR_OPEN;