tools: fix for make dist

- Do not include substitutedd xrdp-chkpriv into tarball
- Dot not install xrdp-chkpriv.in

While here, drop exec permission from *.c source file.

(cherry picked from commit f61a591)

tools/chkpriv/Makefile.am

@@ -3,15 +3,17 @@ xrdppkgdatadir=$(datadir)/xrdp
 pkglibexec_PROGRAMS = \
   xrdp-droppriv
 
-dist_xrdppkgdata_SCRIPTS = \
+nodist_xrdppkgdata_SCRIPTS = \
   xrdp-chkpriv
 
 AM_LDFLAGS = 
 
 AM_CPPFLAGS = \
   -I$(top_srcdir)/common
 
-xrdp_droppriv_SOURCES = xrdp-droppriv.c
+xrdp_droppriv_SOURCES = \
+  xrdp-chkpriv.in \
+  xrdp-droppriv.c
 
 xrdp_droppriv_LDADD = \
   $(top_builddir)/common/libcommon.la
@@ -28,5 +30,5 @@ SUFFIXES = .in
 .in:
 	$(subst_verbose)$(SUBST_VARS) $< > $@
 
-CLEANFILES = xrdp-chkpriv
+CLEANFILES = $(nodist_xrdppkgdata_SCRIPTS)