x86/efi: Delete out-of-date comments of efi_query_variable_store

For now we only ensure about 5kb free space for avoiding our board
refusing boot. But the comment lies that we retain 50% space.

Signed-off-by: Madper Xie <cxie@redhat.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>

arch/x86/platform/efi/efi.c

@@ -1110,9 +1110,8 @@ u64 efi_mem_attributes(unsigned long phys_addr)
 }
 
 /*
- * Some firmware has serious problems when using more than 50% of the EFI
- * variable store, i.e. it triggers bugs that can brick machines. Ensure that
- * we never use more than this safe limit.
+ * Some firmware implementations refuse to boot if there's insufficient space
+ * in the variable store. Ensure that we never use more than a safe limit.
  *
  * Return EFI_SUCCESS if it is safe to write 'size' bytes to the variable
  * store.
@@ -1131,10 +1130,9 @@ efi_status_t efi_query_variable_store(u32 attributes, unsigned long size)
 		return status;
 
 	/*
-	 * Some firmware implementations refuse to boot if there's insufficient
-	 * space in the variable store. We account for that by refusing the
-	 * write if permitting it would reduce the available space to under
-	 * 5KB. This figure was provided by Samsung, so should be safe.
+	 * We account for that by refusing the write if permitting it would
+	 * reduce the available space to under 5KB. This figure was provided by
+	 * Samsung, so should be safe.
 	 */
 	if ((remaining_size - size < EFI_MIN_RESERVE) &&
 		!efi_no_storage_paranoia) {