Fix some 8080 and Z80 code generation issues where DIV and REM weren'…

…t marking

HL as being in use, resulting in occasional register corruption.

src/cowbe/arch8080.cow.ng

@@ -1085,16 +1085,16 @@ gen bc|de|hl := SUB2(bc|de|hl:lhs, CONSTANT():c) uses a
 	aluop2i($lhs, $c.value as uint16, $$, "sui", "sbi");
 }
 
-gen de := DIVU2(de, bc) uses a
+gen de := DIVU2(de, bc) uses a|hl
 		{ dvrmu2(); }
 
 gen hl := REMU2(de, bc) uses a
 		{ dvrmu2(); }
 
-gen de := DIVS2(de, bc) uses a
+gen de := DIVS2(de, bc) uses a|hl
 		{ dvrms2(); }
 
-gen hl := REMS2(de, bc) uses a
+gen hl := REMS2(de, bc) uses a|hl
 		{ dvrms2(); }
 
 gen hl := MUL2(hl, de) uses a|bc

src/cowbe/archz80.cow.ng

@@ -1423,16 +1423,16 @@ gen hl := SUB2(hl:lhs, bc|de:rhs)
 
 %}
 
-gen bc := DIVU2(bc, de) uses a
+gen bc := DIVU2(bc, de) uses a|hl
 		{ E_dvrmu2(); }
 
 gen hl := REMU2(bc, de) uses a
 		{ E_dvrmu2(); }
 
-gen bc := DIVS2(bc, de) uses a
+gen bc := DIVS2(bc, de) uses a|hl
 		{ E_dvrms2(); }
 
-gen de := REMS2(bc, de) uses a
+gen de := REMS2(bc, de) uses a|hl
 		{ E_dvrms2(); }
 
 gen hl := MUL2(de, bc) uses a
@@ -1550,7 +1550,7 @@ gen hlhl := REMU4(bcbc, dede) uses a
 gen bcbc := DIVS4(bcbc, dede) uses a|hlhl
         { E_callhelper("_dvrms4"); }
 
-gen dede := REMS4(bcbc, dede) uses a
+gen dede := REMS4(bcbc, dede) uses a|hlhl
         { E_callhelper("_dvrms4"); }
 
 gen hlhl := AND4(dede, hlhl) uses a