Eliminate some -Wwrite-strings warnings.

dlls/shell32/tests/shelllink.c

@@ -90,7 +90,7 @@ static void test_get_set()
     char mypath[MAX_PATH];
     char buffer[INFOTIPSIZE];
     LPITEMIDLIST pidl, tmp_pidl;
-    char * str;
+    const char * str;
     int i;
     WORD w;
 
@@ -270,13 +270,13 @@ static void test_get_set()
 
 typedef struct
 {
-    char* description;
-    char* workdir;
-    char* path;
+    const char* description;
+    const char* workdir;
+    const char* path;
     LPITEMIDLIST pidl;
-    char* arguments;
+    const char* arguments;
     int   showcmd;
-    char* icon;
+    const char* icon;
     int   icon_id;
     WORD  hotkey;
 } lnk_desc_t;

dlls/shell32/tests/shlfileop.c

@@ -44,7 +44,7 @@ static void InitFunctionPointers(void)
 }
 
 /* creates a file with the specified name for tests */
-void createTestFile(CHAR *name)
+void createTestFile(const CHAR *name)
 {
     HANDLE file;
     DWORD written;
@@ -56,7 +56,7 @@ void createTestFile(CHAR *name)
     CloseHandle(file);
 }
 
-BOOL file_exists(CHAR *name)
+BOOL file_exists(const CHAR *name)
 {
     return GetFileAttributesA(name) != INVALID_FILE_ATTRIBUTES;
 }
@@ -95,7 +95,7 @@ void clean_after_shfo_tests(void)
  files - string with file names, separated by null characters. Ends on a double
  null characters
 */
-void set_curr_dir_path(CHAR *buf, CHAR* files)
+void set_curr_dir_path(CHAR *buf, const CHAR* files)
 {
     buf[0] = 0;
     while (files[0])

dlls/shell32/tests/shlfolder.c

@@ -41,7 +41,7 @@
 IMalloc *ppM;
 
 /* creates a file with the specified name for tests */
-void CreateTestFile(CHAR *name)
+void CreateTestFile(const CHAR *name)
 {
     HANDLE file;
     DWORD written;