Allow read of partial requestFrom data

WireKinetis.cpp

 			if (millis() - wait_begin > 5) {
 				port.C1 = 0;
 				port.C1 = I2C_C1_IICEN;
+				rxBufferLength = count;
 				return count; // clock stretch too long (during data)
 			}
 		}
 		if (millis() - wait_begin > 5) {
 			port.C1 = 0;
 			port.C1 = I2C_C1_IICEN;
+			rxBufferLength = count;
 			return count; // clock stretch too long (during data)
 		}
 	}