Move tilegx, tilepro, and linux-generic from ports to libc.

I've moved the TILE-Gx and TILEPro ports to the main sysdeps hierarchy,
along with the linux-generic ports infrastructure.  Beyond the README
update, the move was just

    git mv ports/sysdeps/tile sysdeps/tile
    git mv ports/sysdeps/unix/sysv/linux/tile \
      sysdeps/unix/sysv/linux/tile
    git mv ports/sysdeps/unix/sysv/linux/generic \
      sysdeps/unix/sysv/linux/generic

I updated the relevant ChangeLogs along the lines of the ARM move
in commit c6bfe5c4d75 and tested the 64-bit tilegx build to confirm that
there were no changes in "objdump -dr" output in the shared objects.

1 files changed, 11 insertions, 0 deletions

diff --git a/sysdeps/tile/bits/endian.h b/sysdeps/tile/bits/endian.h
new file mode 100644
index 0000000000..835042a7ac
--- /dev/null
+++ b/sysdeps/tile/bits/endian.h
@@ -0,0 +1,11 @@
+/* Set endianness for tile.  */
+
+#ifndef _ENDIAN_H
+# error "Never use <bits/endian.h> directly; include <endian.h> instead."
+#endif
+
+#if defined __BIG_ENDIAN__
+# define __BYTE_ORDER __BIG_ENDIAN
+#else
+# define __BYTE_ORDER __LITTLE_ENDIAN
+#endif