[#1868] Reload config for pprof and metrics on SIGHUP

Signed-off-by: Anton Nikiforov <an.nikiforov@yadro.com>

cmd/frostfs-node/closer.go

@@ -0,0 +1,25 @@
+package main
+
+type closer struct {
+	name string
+	fn   func()
+}
+
+func getCloser(c *cfg, name string) *closer {
+	for _, clsr := range c.closers {
+		if clsr.name == name {
+			return &clsr
+		}
+	}
+	return nil
+}
+
+func delCloser(c *cfg, name string) {
+	for i, clsr := range c.closers {
+		if clsr.name == name {
+			c.closers[i] = c.closers[len(c.closers)-1]
+			c.closers = c.closers[:len(c.closers)-1]
+			return
+		}
+	}
+}