Replace incorrect $$ with $ in README.md

README.md

@@ -7,6 +7,6 @@ Base project containing apps and drivers for the mangOH hardware
 1. Download and install the appropriate toolchain from [source.sierrawireless.com](https://source.sierrawireless.com/resources/legato/downloads/)
 1. Get the Legato source code as described by the [Legato README](https://github.com/legatoproject/legato-af/blob/master/README.md)
 1. Clone the mangOH source code by running `git clone --recursive git://github.com/mangOH/mangOH`
-1. `cd` into the Legato working folder and run the following command to build a system for the mangOH Red: `make wp85 SDEF_TO_USE=$$MANGOH_ROOT/mangOH_Red.sdef MKSYS_FLAGS="-s $$MANGOH_ROOT/apps/GpioExpander/gpioExpanderService -s $$MANGOH_ROOT/apps/RedSensorToCloud"`
+1. `cd` into the Legato working folder and run the following command to build a system for the mangOH Red: `make wp85 SDEF_TO_USE=$MANGOH_ROOT/mangOH_Red.sdef MKSYS_FLAGS="-s $MANGOH_ROOT/apps/GpioExpander/gpioExpanderService -s $MANGOH_ROOT/apps/RedSensorToCloud"`
 1. Run `./bin/legs` to put the Legato tools into `$PATH`
 1. Run `instlegato wp85 192.168.2.2` to install the system onto the mangOH connected via a USB cable to the CF3 USB port.