Handle EROFS/ETXTBSY as permission denied in `fileAccess` (re #8741)

This extends `System.Posix.Files.`access` to map EROFS & ETXTBSY to
mean permission denied just like EACCESS.

Based on a patch by Alain O'Dea and comments by Duncan Coutts

Authored-by: Alain O'Dea <alain.odea@verafin.com>
Signed-off-by: Herbert Valerio Riedel <hvr@gnu.org>

System/Posix/Files.hsc

@@ -151,7 +151,7 @@ access name flags =
     if (r == 0)
 	then return True
 	else do err <- getErrno
-	        if (err == eACCES)
+	        if (err == eACCES || err == eROFS || err == eTXTBSY)
 		   then return False
 		   else throwErrnoPath "fileAccess" name
 

changelog.md

+## 2.7.0.1
+
+  * Handle EROFS and ETXTBSY as (non-exceptional) permission denied in `fileAccess`
+
 ## 2.7.0.0  *Nov 2013*
 
   * New `forkProcessWithUnmask` function in the style of `forkIOWithUnmask`