rename "sp" to "spc", avoid conflict with 4510 opcodes

test/asm/opcodes/m740-opcodes.s

@@ -36,7 +36,7 @@
    bbr1    $12,*+122   ; clb 0,zp
    jsr     $3456
    and     ($12,x)
-   .byte   $22,$00,$00 ; jsr sp
+   .byte   $22,$00,$00 ; jsr spc
    .byte   $23,$00,$00 ; bbs 1,a
    bit     $12
    and     $12

test/val/bug1652-optimizer.c

@@ -10,9 +10,9 @@ before:
         jsr     pusha
         ldy     #$01
         ldx     #$00
-        lda     (sp),y
+        lda     (spc),y
         beq     L0005
-        lda     (sp,x)
+        lda     (spc,x)
         beq     L0005
         txa
         jmp     incsp2          ; <--
@@ -24,9 +24,9 @@ after:
         jsr     pusha
         ldy     #$01
         ldx     #$00
-        lda     (sp),y
+        lda     (spc),y
         beq     L0004
-        lda     (sp,x)
+        lda     (spc,x)
         beq     L0004
         txa
         jmp     L0001            ; <--

test/val/cq85.c

@@ -62,7 +62,7 @@ int s85(struct defs *pd0){
      struct tnode *right;
    };
 
-   struct tnode s1, s2, *sp;
+   struct tnode s1, s2, *spc;
 
    struct{
      char cdummy;