nptl/Makefile.in: Fix the build break caused by UCLIBC_CTOR_DTOR enabling

Extra / somehow does not match the target and complains that
$(top_builddir)libpthread/nptl/sysdeps/pthread/crti.o has no rules to
build

Signed-off-by: Khem Raj <raj.khem@gmail.com>

libpthread/nptl/Makefile.in

@@ -64,8 +64,8 @@ endif
 librt-so-y += $(librt_OBJS:.o=.oS) $(librt-pt-shared-only-routines-y:.o=.oS)
 
 ifeq ($(UCLIBC_CTOR_DTOR),y)
-START_FILE-libpthread.so := $(top_builddir)/libpthread/nptl/sysdeps/pthread/crti.o
-END_FILE-libpthread.so := $(top_builddir)/libpthread/nptl/sysdeps/pthread/crtn.o
+START_FILE-libpthread.so := $(top_builddir)libpthread/nptl/sysdeps/pthread/crti.o
+END_FILE-libpthread.so := $(top_builddir)libpthread/nptl/sysdeps/pthread/crtn.o
 LDFLAGS-libpthread.so += -nostartfiles
 $(top_builddir)lib/libpthread.so: | $(START_FILE-libpthread.so) $(END_FILE-libpthread.so)
 endif