advpack: Constify some variables

[Andrew Talbot]

Changelog:
    advpack: Constify some variables.

diff -urN a/dlls/advpack/files.c b/dlls/advpack/files.c
--- a/dlls/advpack/files.c	2006-10-23 17:32:15.000000000 +0100
+++ b/dlls/advpack/files.c	2007-03-12 18:43:32.000000000 +0000
@@ -603,7 +603,7 @@
 }
 
 /* determines whether szFile is in the NULL-separated szFileList */
-static BOOL file_in_list(LPSTR szFile, LPSTR szFileList)
+static BOOL file_in_list(LPCSTR szFile, LPCSTR szFileList)
 {
     DWORD dwLen = lstrlenA(szFile);
     DWORD dwTestLen;
@@ -627,7 +627,7 @@
 /* removes nodes from the linked list that aren't specified in szFileList
  * returns the number of files that are in both the linked list and szFileList
  */
-static DWORD fill_file_list(EXTRACTdest *extractDest, LPCSTR szCabName, LPSTR szFileList)
+static DWORD fill_file_list(EXTRACTdest *extractDest, LPCSTR szCabName, LPCSTR szFileList)
 {
     DWORD dwNumFound = 0;
     struct ExtractFileList *pNode;
diff -urN a/dlls/advpack/install.c b/dlls/advpack/install.c
--- a/dlls/advpack/install.c	2006-11-07 17:36:34.000000000 +0000
+++ b/dlls/advpack/install.c	2007-03-12 20:28:20.000000000 +0000
@@ -214,7 +214,7 @@
     return token;
 }
 
-static BOOL is_full_path(LPWSTR path)
+static BOOL is_full_path(LPCWSTR path)
 {
     const int MIN_PATH_LEN = 3;
 
@@ -229,7 +229,7 @@
 
 /* retrieves the contents of a field, dynamically growing the buffer if necessary */
 static WCHAR *get_field_string(INFCONTEXT *context, DWORD index, WCHAR *buffer,
-                               WCHAR *static_buffer, DWORD *size)
+                               const WCHAR *static_buffer, DWORD *size)
 {
     DWORD required;
 
diff -urN a/dlls/advpack/reg.c b/dlls/advpack/reg.c
--- a/dlls/advpack/reg.c	2006-10-07 17:37:13.000000000 +0100
+++ b/dlls/advpack/reg.c	2007-03-12 19:05:42.000000000 +0000
@@ -98,7 +98,7 @@
     return FALSE;
 }
 
-static void strentry_atow(STRENTRYA *aentry, STRENTRYW *wentry)
+static void strentry_atow(const STRENTRYA *aentry, STRENTRYW *wentry)
 {
     DWORD name_len, val_len;
 
@@ -171,7 +171,7 @@
     return hr;
 }
 
-static HRESULT write_predefined_strings(HMODULE hm, LPWSTR ini_path)
+static HRESULT write_predefined_strings(HMODULE hm, LPCWSTR ini_path)
 {
     WCHAR mod_path[MAX_PATH + 2];
     WCHAR sys_mod_path[MAX_PATH + 2];