Remove useless linux64 suffix

See:
https://github.com/arduino/Arduino/wiki/Arduino-IDE-1.5-3rd-party-Hardware-specification#automatic-property-override-for-specific-os

Suffixes supported are .linux, .windows and .macosx.

Signed-off-by: Frederic Pillon <[email protected]>

Author: fpistm

platform.txt

@@ -158,7 +158,6 @@ tools.massStorageCopy.cmd.macosx=massStorageCopyMacOsX
 tools.massStorageCopy.path={runtime.tools.STM32Tools.path}/tools/win
 tools.massStorageCopy.path.macosx={runtime.tools.STM32Tools.path}/tools/macosx
 tools.massStorageCopy.path.linux={runtime.tools.STM32Tools.path}/tools/linux
-tools.massStorageCopy.path.linux64={runtime.tools.STM32Tools.path}/tools/linux
 tools.massStorageCopy.upload.params.verbose=
 tools.massStorageCopy.upload.params.quiet=
 tools.massStorageCopy.upload.pattern="{path}/{cmd}" {upload.verbose} -I "{build.path}/{build.project_name}.bin" -O "{node}"
@@ -198,7 +197,6 @@ tools.maple_upload.cmd.windows=maple_upload.bat
 tools.maple_upload.path={runtime.tools.STM32Tools.path}/tools/win
 tools.maple_upload.path.macosx={runtime.tools.STM32Tools.path}/tools/macosx
 tools.maple_upload.path.linux={runtime.tools.STM32Tools.path}/tools/linux
-tools.maple_upload.path.linux64={runtime.tools.STM32Tools.path}/tools/linux64
 tools.maple_upload.upload.params.verbose=-d
 tools.maple_upload.upload.params.quiet=n
 tools.maple_upload.upload.pattern="{path}/{cmd}" {serial.port.file} {upload.altID} {upload.usbID} "{build.path}/{build.project_name}.bin"