Add endian option for configure.

For the payload project, the endian check does not work(due to some
problem with the hardfloating point settings for stm32f7). So now
we can pass in the endianness as an option when needed.

Author: joehowarth17

Diff for: wscript

@@ -63,6 +63,7 @@ def options(ctx):
     # OS    
     gr.add_option('--with-os', metavar='OS', default='posix', help='Set operating system. Must be either \'posix\', \'macosx\', \'windows\' or \'freertos\'')
     gr.add_option('--enable-init-shutdown', action='store_true', help='Use init system commands for shutdown/reboot')
+    gr.add_option('--endian', metavar='endianChoice', default='', help='Set endianess. Should be little or big')
 
     # Options
     gr.add_option('--with-rdp-max-window', metavar='SIZE', type=int, default=20, help='Set maximum window size for RDP')
@@ -216,7 +217,11 @@ def configure(ctx):
     ctx.define_cond('CSP_LOG_LEVEL_ERROR', ctx.options.with_loglevel in ('debug', 'info', 'warn', 'error'))
 
     # Check compiler endianness
-    endianness = ctx.check_endianness()
+    if ctx.options.endian == '':
+        endianness = ctx.check_endianness()
+    else:
+        endianness = ctx.options.endian
+
     ctx.define_cond('CSP_LITTLE_ENDIAN', endianness == 'little')
     ctx.define_cond('CSP_BIG_ENDIAN', endianness == 'big')