add: minilibc to the examples

examples/minilibc/strrchr.pasm

@@ -0,0 +1,26 @@
+; strrchr
+
+set str "hello, world !\0"
+
+found:
+mov a2, a1
+ret
+
+end_:
+push a2
+call print
+mov eax, a2
+end
+
+main:
+mov a1, str 
+mov a2, 0
+mov a3, 111 ; 'o'
+
+loop:
+cmp (char)*a1, 0
+je end_
+cmp (char)a3, (char)*a1
+je found
+add a1, 1
+jmp loop