Pull request: dhcpd: add ips and text option types

Updates #2385.

Squashed commit of the following:

commit ce8467f1c013c6b3fef59667084e2c6569a7213c
Author: Ainar Garipov <A.Garipov@AdGuard.COM>
Date:   Mon Mar 15 19:02:17 2021 +0300

    dhcpd: add ips and text option types

internal/dhcpd/dhcpd_test.go

@@ -124,67 +124,3 @@ func TestNormalizeLeases(t *testing.T) {
 	assert.Equal(t, leases[1].HWAddr, staticLeases[1].HWAddr)
 	assert.Equal(t, leases[2].HWAddr, dynLeases[1].HWAddr)
 }
-
-func TestOptions(t *testing.T) {
-	testCases := []struct {
-		name     string
-		optStr   string
-		wantVal  []byte
-		wantCode uint8
-	}{{
-		name:     "success_hex",
-		optStr:   "12 hex abcdef",
-		wantVal:  []byte{0xab, 0xcd, 0xef},
-		wantCode: 12,
-	}, {
-		name:     "bad_hex",
-		optStr:   "12 hex abcdefx",
-		wantVal:  nil,
-		wantCode: 0,
-	}, {
-		name:     "success_ip",
-		optStr:   "123 ip 1.2.3.4",
-		wantVal:  net.IP{1, 2, 3, 4},
-		wantCode: 123,
-	}, {
-		name:   "success_ipv6",
-		optStr: "123 ip ::1234",
-		wantVal: net.IP{
-			0, 0, 0, 0,
-			0, 0, 0, 0,
-			0, 0, 0, 0,
-			0, 0, 0x12, 0x34,
-		},
-		wantCode: 123,
-	}, {
-		name:     "bad_code",
-		optStr:   "256 ip 1.1.1.1",
-		wantVal:  nil,
-		wantCode: 0,
-	}, {
-		name:     "negative_code",
-		optStr:   "-1 ip 1.1.1.1",
-		wantVal:  nil,
-		wantCode: 0,
-	}, {
-		name:     "bad_ip",
-		optStr:   "12 ip 1.1.1.1x",
-		wantVal:  nil,
-		wantCode: 0,
-	}, {
-		name:     "bad_mode",
-		wantVal:  nil,
-		optStr:   "12 x 1.1.1.1",
-		wantCode: 0,
-	}}
-
-	for _, tc := range testCases {
-		t.Run(tc.name, func(t *testing.T) {
-			code, val := parseOptionString(tc.optStr)
-			require.Equal(t, tc.wantCode, code)
-			if tc.wantVal != nil {
-				assert.Equal(t, tc.wantVal, val)
-			}
-		})
-	}
-}