i2c scan logic change

I patched generic_linux/i2c.py:I2C.scan() to:
	•	scan only 0x08..0x77
	•	try write_quick() first, fall back to read_byte()

Author: mikeysklar

src/adafruit_blinka/microcontroller/generic_linux/i2c.py

@@ -41,14 +41,16 @@ def __init__(self, bus_num, mode=MASTER, baudrate=None):
     # pylint: enable=unused-argument
 
     def scan(self):
-        """Try to read a byte from each address, if you get an OSError
-        it means the device isnt there"""
+        """Probe each address; return those that ACK."""
         found = []
-        for addr in range(0, 0x80):
+        for addr in range(0x08, 0x78):
             try:
-                self._i2c_bus.read_byte(addr)
+                self._i2c_bus.write_quick(addr)
             except OSError:
-                continue
+                try:
+                    self._i2c_bus.read_byte(addr)
+                except OSError:
+                    continue
             found.append(addr)
         return found