racket: Add missing patches

Follow-up of commit ede8de9548.

packages/racket/bc-configure.patch

@@ -0,0 +1,11 @@
+--- a/src/bc/configure
++++ b/src/bc/configure
+@@ -5019,7 +5019,7 @@
+     fi
+     ;;
+   linux*)
+-    LIBS="$LIBS -ldl -lm -lrt -rdynamic"
++    LIBS="$LIBS -ldl -lm -rdynamic"
+     DYN_CFLAGS="-fPIC"
+     curses_portable_link="/usr/lib/${host_cpu}-${host_os}/libncurses.a /usr/lib/${host_cpu}-${host_os}/libtermcap.a"
+     case "$host_cpu" in

packages/racket/configure.patch

@@ -0,0 +1,10 @@
+--- a/src/configure
++++ b/src/configure
+@@ -12,7 +12,6 @@
+ supplied_racket=no
+ supplied_scheme=no
+ enable_boothelp=
+-CC_FOR_BUILD='$(CC) -O2'
+ 
+ # We don't have to detect conflicts like `--enable-csdefault --enable-bcdefault`,
+ # since the `configure` scripts will do that, but  we have to figure out which