z80: remove call indirections in tight spots

blk/216

@@ -1,7 +1,7 @@
 : OP1 CREATE C, DOES> C@ A, ;
 0xf3 OP1 DI,                   0xfb OP1 EI,
 0xeb OP1 EXDEHL,               0xd9 OP1 EXX,
-0x08 OP1 EXAFAF',
+0x08 OP1 EXAFAF',              0xe3 OP1 EX(SP)HL,
 0x76 OP1 HALT,                 0xe9 OP1 JP(HL),
 0x12 OP1 LD(DE)A,              0x1a OP1 LDA(DE),
 0x02 OP1 LD(BC)A,              0x0a OP1 LDA(BC),

blk/297

@@ -1,4 +1,4 @@
-PC ORG @ 0x12 + ! ( pushRS )
+L4 BSET PC ORG @ 0x12 + ! ( pushRS )
     IX INCss,
     IX INCss,
     0 IX+ L LDIXYr,

blk/299

@@ -1,4 +1,4 @@
-PC ORG @ 0x1e + ! ( chkPS )
+L1 BSET PC ORG @ 0x1e + ! ( chkPS )
 ( Note that you only need to call this in words that push
   back to PSP. If they don't, calling chkPS is redundant with
   check in next )

blk/300

@@ -3,7 +3,7 @@ PC ORG @ 0x1b + ! ( next )
   we jump to current IP, but we also take care of increasing
   it by 2 before jumping. )
 	( Before we continue: are stacks within bounds? )
-    0x1d BCALL, ( chkPS )
+    L1 @ ( chkPS ) BCALL,
     ( check RS )
     IX PUSHqq, HL POPqq,
     DE RS_ADDR LDddnn,

blk/302

@@ -3,7 +3,7 @@ L1 BSET PC ORG @ 0x0f + ! ( compiledWord )
   2. Set new IP to the second atom of the list
   3. Execute the first atom of the list. )
     IY PUSHqq, HL POPqq, ( <-- IP )
-    0x11 BCALL,      ( 11 == pushRS )
+    L4 @ ( pushRS ) BCALL,
     EXDEHL,          ( HL points to PFA )
 ( While we inc, dereference into DE for execute call later. )
     LDDE(HL),