Fix warnings during debuginfo generation

Commit f3b87dde removed a needed 'shift' from mingw-find-debuginfo.sh,
which made debuginfo generation often complain about directories not
found.

Add the 'shift' back and at the same time improve argument parsing error
messages.

mingw-filesystem.spec

@@ -2,7 +2,7 @@
 
 Name:           mingw-filesystem
 Version:        95
-Release:        5%{?dist}
+Release:        6%{?dist}
 Summary:        MinGW cross compiler base filesystem and environment
 
 Group:          Development/Libraries
@@ -250,6 +250,9 @@ install -m 0644 %{SOURCE12} $RPM_BUILD_ROOT%{_datadir}/mingw/
 
 
 %changelog
+* Fri Mar 16 2012 Kalev Lember <kalevlember@gmail.com> - 95-6
+- Fix warnings during debuginfo generation
+
 * Fri Mar 16 2012 Kalev Lember <kalevlember@gmail.com> - 95-5
 - Simplify the mingw_make_install macro, also moving it to the deprecated
   section

mingw-find-debuginfo.sh

@@ -2,10 +2,14 @@
 # mingw-find-debuginfo.sh - automagically generate debug info and file list
 # for inclusion in an rpm spec file for mingw-* packages.
 
-if [ -z "$1" ] ; then BUILDDIR="."
-else BUILDDIR=$1
+if [ "$#" -lt 2 ] ; then
+    echo "Usage: $0 <BUILDDIR> [TARGET]..."
+    exit 1
 fi
 
+BUILDDIR=$1
+shift
+
 for f in `find $RPM_BUILD_ROOT -type f -name "*.exe" -or -name "*.dll"`
 do
 	case $(mingw-objdump -h $f 2>/dev/null | egrep -o '(debug[\.a-z_]*|gnu.version)') in