[gnumeric] Compilation: constify.

[Morten Welinder <mortenw src gnome org>]

commit b793ef197ea7c27ee6c2fd23abcdc05f98bcd4aa
Author: Morten Welinder <terra gnome org>
Date:   Thu May 14 19:23:19 2015 -0400

    Compilation: constify.

 plugins/excel/ChangeLog       |    2 ++
 plugins/excel/ms-excel-read.c |    6 +++---
 2 files changed, 5 insertions(+), 3 deletions(-)
---
diff --git a/plugins/excel/ChangeLog b/plugins/excel/ChangeLog
index bcfa76f..bf9a73c 100644
--- a/plugins/excel/ChangeLog
+++ b/plugins/excel/ChangeLog
@@ -1,5 +1,7 @@
 2015-05-14  Morten Welinder  <terra gnome org>
 
+       * ms-excel-read.c (excel_read_FILEPASS): Constify.
+
        * md5.c (md5_read_ctx): Don't require aligned memory.
 
 2015-05-13  Morten Welinder  <terra gnome org>
diff --git a/plugins/excel/ms-excel-read.c b/plugins/excel/ms-excel-read.c
index dcb7a95..5b8cf6d 100644
--- a/plugins/excel/ms-excel-read.c
+++ b/plugins/excel/ms-excel-read.c
@@ -6298,7 +6298,7 @@ excel_read_EXTERNSHEET (BiffQuery const *q, GnmXLImporter *importer,
 /* FILEPASS, ask the user for a password if necessary
  * return value is an error string, or NULL for success
  */
-static char *
+static const char *
 excel_read_FILEPASS (BiffQuery *q, GnmXLImporter *importer)
 {
        /* files with workbook protection are encrypted using a
@@ -6796,7 +6796,7 @@ excel_read_sheet (BiffQuery *q, GnmXLImporter *importer,
                case BIFF_STYLE:        break;
                case BIFF_1904:         excel_read_1904 (q, importer);  break;
                case BIFF_FILEPASS: {
-                       char *problem = excel_read_FILEPASS (q, importer);
+                       const char *problem = excel_read_FILEPASS (q, importer);
                        if (problem != NULL) {
                                go_cmd_context_error_import (GO_CMD_CONTEXT (importer->context), problem);
                                return FALSE;
@@ -7136,7 +7136,7 @@ excel_read_workbook (GOIOContext *context, WorkbookView *wb_view,
        BiffQuery *q;
        MsBiffBofData *ver = NULL;
        unsigned current_sheet = 0;
-       char *problem_loading = NULL;
+       const char *problem_loading = NULL;
        gboolean stop_loading = FALSE;
        gboolean prev_was_eof = FALSE;