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, 17 insertions, 0 deletions

diff --git a/sysdeps/unix/sysv/linux/tile/Versions b/sysdeps/unix/sysv/linux/tile/Versions
new file mode 100644
index 0000000000..9b40d2839f
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/tile/Versions
@@ -0,0 +1,17 @@
+ld {
+  GLIBC_PRIVATE {
+    # used for loading by static libraries
+    _dl_var_init;
+  }
+}
+libc {
+  GLIBC_2.12 {
+    _flush_cache;
+    cacheflush;
+    fallocate64;
+    set_dataplane;
+  }
+  GLIBC_PRIVATE {
+    __syscall_error;
+  }
+}