fix devicestr call, so related posix function work on cbm targets

libsrc/cbm/initcwd.s

@@ -9,8 +9,6 @@
         .import         pusha0, tosudiva0
         .importzp       sreg, ptr1, ptr2
 
-        .macpack        generic
-
 initcwd:
         lda     #<__cwd
         ldx     #>__cwd
@@ -27,15 +25,20 @@ devicestr:
         lda     #10
         jsr     tosudiva0
         ldy     #0
-        lda     sreg
+        tax                     ; result of the division (lsb)
-        beq     @L0             ; >=10
+        beq     @L0             ; < 10
-        add     #'0'
+
+        clc
+        adc     #'0'
         sta     (ptr2),y
         iny
-@L0:    lda     ptr1            ; rem
+@L0:
-        add     #'0'
+        lda     sreg            ; reminder of the division
+        clc
+        adc     #'0'
         sta     (ptr2),y
         iny
-        lda     #0
+
+        lda     #0              ; terminating 0
         sta     (ptr2),y
         rts