gcode: Add minval/maxval/above/below options to get_X parsers

Add value checking to gcode parameter parsing code.

Signed-off-by: Kevin O'Connor <kevin@koconnor.net>

klippy/extras/output_pin.py

@@ -49,14 +49,13 @@ class PrinterOutputPin:
             return pin.cmd_SET_PIN(params)
         if self.is_static:
             raise self.gcode.error("Static pin can not be changed at run-time")
-        value = self.gcode.get_float('VALUE', params) / self.scale
+        value = self.gcode.get_float('VALUE', params, minval=0., maxval=1.)
+        value /= self.scale
         if value == self.last_value:
             return
         print_time = self.printer.lookup_object('toolhead').get_last_move_time()
         print_time = max(print_time, self.last_value_time + PIN_MIN_TIME)
         if self.is_pwm:
-            if value < 0. or value > 1.:
-                raise self.gcode.error("Invalid pin value")
             self.mcu_pin.set_pwm(print_time, value)
         else:
             if value not in [0., 1.]:

klippy/extras/virtual_sdcard.py

@@ -102,7 +102,7 @@ class VirtualSD:
         # Set SD position
         if self.work_timer is not None:
             raise self.gcode.error("SD busy")
-        pos = self.gcode.get_int('S', params)
+        pos = self.gcode.get_int('S', params, minval=0)
         self.file_position = pos
     def cmd_M27(self, params):
         # Report SD print status