tests: Make float and framebuf tests skip or run on big-endian archs.

Signed-off-by: Damien George <damien@micropython.org>

tests/float/bytes_construct_endian.py

@@ -0,0 +1,12 @@
+# test construction of bytes from array with float type
+
+try:
+    from uarray import array
+except ImportError:
+    try:
+        from array import array
+    except ImportError:
+        print("SKIP")
+        raise SystemExit
+
+print(bytes(array("f", [1, 2.3])))