Fix svnversion.h generation

Dollar signs should be written as two dollar signs to be interpreted by
the shell rather than by the make.


git-svn-id: http://madwifi-project.org/svn/madwifi/trunk@3225 0192ed92-7a03-0410-a25b-9323aeb14dbd

Makefile

@@ -66,13 +66,13 @@ endif
 .PHONY: svnversion.h
 svnversion.h:
 	@if [ -d .svn ]; then \
-		ver=$(svnversion -nc . | sed -e 's/^[^:]*://;s/[A-Za-z]//'); \
+		ver=$$(svnversion -nc . | sed -e 's/^[^:]*://;s/[A-Za-z]//'); \
 		echo "#define SVNVERSION \"svn r$$ver\"" > $@.tmp; \
 	elif [ -d .git ]; then \
-		ver=$(git svn log | head -n2 | tail -n1 | cut -d\  -f1); \
+		ver=$$(git svn log | head -n2 | tail -n1 | cut -d\  -f1); \
 		echo "#define SVNVERSION \"svn $$ver\"" > $@.tmp; \
 	elif [ -s SNAPSHOT ]; then \
-		ver=$(sed -e '/^Revision: */!d;s///;q' SNAPSHOT); \
+		ver=$$(sed -e '/^Revision: */!d;s///;q' SNAPSHOT); \
 		echo "#define SVNVERSION \"svn r$$ver\"" > $@.tmp; \
 	else \
 		touch $@.tmp; \