libc/uClibc: move content of do_libc_headers into do_libc_start_files

It is unnecessary to split C library preparation into two steps, as only
one really makes sense. So, do_libc_headers is bound to be withdrawn
short-term, in favor of do_libc_start_files.

uClibc already had all its start files installation in do_libc_headers, and
do_libc_start_files was empty, just migrate the content of the former into
the latter.

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@anciens.enib.fr>

--- glibc-2_9.orig/nptl/init.c	2007-10-15 22:25:25.000000000 +0200

+++ glibc-2_9/nptl/init.c	2010-08-18 10:46:06.109098646 +0200

@@ -236,7 +236,7 @@

 /* This can be set by the debugger before initialization is complete.  */

-static bool __nptl_initial_report_events;

+static bool __nptl_initial_report_events __attribute_used__;

 void

 __pthread_initialize_minimal_internal (void)