x86/mtrr: drop positive_have_wrcomb()

The only call to have_wrcomb() was always to the generic implementation.
positive_have_wrcomb() was unused.

Signed-off-by: Doug Goldstein <cardoe@cardoe.com>
Acked-by: Jan Beulich <jbeulich@suse.com>

xen/arch/x86/cpu/mtrr/generic.c

@@ -557,11 +557,6 @@ static int generic_have_wrcomb(void)
 	return (config & (1ULL << 10));
 }
 
-int positive_have_wrcomb(void)
-{
-	return 1;
-}
-
 /* generic structure...
  */
 const struct mtrr_ops generic_mtrr_ops = {

xen/arch/x86/cpu/mtrr/mtrr.h

@@ -31,8 +31,6 @@ extern int generic_validate_add_page(unsigned long base, unsigned long size,
 
 extern const struct mtrr_ops generic_mtrr_ops;
 
-extern int positive_have_wrcomb(void);
-
 /* library functions for processor-specific routines */
 struct set_mtrr_context {
 	unsigned long flags;