Notes about how powerpc/bits was constructed.

libc/sysdeps/linux/powerpc/README.bits

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+
+include/bits is mostly the same as glibc-2.2.4.  The glibc-2.2.4
+versions can be accessed with the tag glibc224.
+
+Major differences:
+
+  - termios.h is from the Linux kernel, not glibc, because glibc has
+    a very strange legacy conversion layer, which we ignore.
+
+  - syscall.h is deleted, because it is autogenerated in uClibc
+
+  - syscalls.h is added.
+
+