patch 9.0.0384: Covertity still complains about using return value of getc()

Problem:    Covertity still complains about using return value of getc().
Solution:   Check for EOF.
diff --git a/src/spellfile.c b/src/spellfile.c
index b248b07..3c934fc 100644
--- a/src/spellfile.c
+++ b/src/spellfile.c
@@ -846,7 +846,7 @@
     if (len > MAXREGIONS * 2)
 	return SP_FORMERROR;
     for (i = 0; i < len; ++i)
-	lp->sl_regions[i] = c = getc(fd);	// <regionname>
+	lp->sl_regions[i] = (c = getc(fd)) == EOF ? 0 : c; // <regionname>
     lp->sl_regions[len] = NUL;
     return c == EOF ? SP_TRUNCERROR : 0;
 }
@@ -927,7 +927,7 @@
 	    buf[0] = '^';	    // always match at one position only
 	    p = buf + 1;
 	    while (n-- > 0)
-		*p++ = c = getc(fd);		    // <condstr>
+		*p++ = (c = getc(fd)) == EOF ? 0 : c;	    // <condstr>
 	    if (c == EOF)
 		break;
 	    *p = NUL;
@@ -1067,7 +1067,7 @@
 	    // store the char we got while checking for end of sm_lead
 	    *p++ = c;
 	for (++i; i < ccnt; ++i)
-	    *p++ = c = getc(fd);		// <salfrom>
+	    *p++ = (c = getc(fd)) == EOF ? 0 : c;	// <salfrom>
 	*p++ = NUL;
 
 	// <saltolen> <salto>