fix Swashbuckler highscore saving

src/constants.a

@@ -8,7 +8,7 @@
 ; LC RAM BANK 1
 ; D000..E8C9 - persistent data structures (gGlobalPrefsStore, gGamesListStore)
 ; ...unused...
-; E91D..FFF1 - main program code
+; E912..FFF1 - main program code
 ; FFF2..FFF9 - API functions and global constants available for main program
 ;              code, prelaunchers, transition effects, &c.
 ;              (Wait/UnwaitForVBL, MockingboardStuff, MachineStatus)

src/prodos.impl.lc2.a

@@ -280,20 +280,12 @@ resetval=$f0
          jsr   @set_rdwrbuff
          plp
          bcc   @skip_align
-         lda   sizelo
-         adc   #$fe
-         lda   sizehi
-         adc   #1
-         and   #$fe
-         sta   sizehi
-         lda   bleftlo
-         adc   #$ff
+         ldx   #sizelo
+         jsr   @round
          lda   #0
-         sta   bleftlo
-         lda   blefthi
-         adc   #1
-         and   #$fe
-         sta   blefthi
+         sta   sizelo
+         ldx   #bleftlo
+         jsr   @round
 
 @skip_align
          jsr   hddrdwrpart
@@ -371,6 +363,16 @@ resetval=$f0
          iny
          rts
 
+@round
+         clc
+         lda   $0,x
+         adc   #$ff
+         lda   $1,x
+         adc   #1
+         and   #$fe
+         sta   $1,x
+         rts
+
 @swap_zp
          ldx   #last_zp-first_zp
 @save_zp