mb/google/volteer/variants/delbin: Enhance I2C5 bus freq closer 400 kHz

The current I2C5 bus frequency is 367 kHZ, which does not meet the spec.
This change updates scl_lcnt, scl_hcnt, scl_hcnt value for I2C5 to bring
the bus frequency closer to 400kHz.

BUG=b:173670150
TEST=Verified that I2C5 frequency is between 386-387kHz.

Signed-off-by: Frank Chu <frank_chu@pegatron.corp-partner.google.com>
Change-Id: I6d60abe15645dc51ed9ee30975d2521b8940c2d0
Reviewed-on: https://review.coreboot.org/c/coreboot/+/47736
Reviewed-by: Zhuohao Lee <zhuohao@google.com>
Reviewed-by: Zhuohao Lee <zhuohao@chromium.org>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/mainboard/google/volteer/variants/delbin/overridetree.cb

@@ -2,6 +2,49 @@ chip soc/intel/tigerlake
 	register "DdiPort1Hpd" = "0"
 	register "DdiPort2Hpd" = "0"
 
+	#+-------------------+---------------------------+
+	#| Field             |  Value                    |
+	#+-------------------+---------------------------+
+	#| chipset_lockdown  | CHIPSET_LOCKDOWN_COREBOOT |
+	#| GSPI0             | cr50 TPM. Early init is   |
+	#|                   | required to set up a BAR  |
+	#|                   | for TPM communication     |
+	#|                   | before memory is up       |
+	#| I2C0              | Audio                     |
+	#| I2C1              | Touchscreen               |
+	#| I2C2              | WLAN, SAR0                |
+	#| I2C3              | Camera, SAR1              |
+	#| I2C5              | Trackpad                  |
+	#+-------------------+---------------------------+
+	register "common_soc_config" = "{
+		.chipset_lockdown = CHIPSET_LOCKDOWN_COREBOOT,
+		.gspi[0] = {
+			.speed_mhz = 1,
+			.early_init = 1,
+		},
+		.i2c[0] = {
+			.speed = I2C_SPEED_FAST,
+		},
+		.i2c[1] = {
+			.speed = I2C_SPEED_FAST,
+		},
+		.i2c[2] = {
+			.speed = I2C_SPEED_FAST,
+		},
+		.i2c[3] = {
+			.speed = I2C_SPEED_FAST,
+		},
+		.i2c[5] = {
+			.speed = I2C_SPEED_FAST,
+			.speed_config[0] = {
+				.speed = I2C_SPEED_FAST,
+				.scl_lcnt = 163,
+				.scl_hcnt = 75,
+				.sda_hold = 36,
+			},
+		},
+	}"
+
 	# Acoustic settings
 	register "AcousticNoiseMitigation" = "1"
 	register "SlowSlewRate[VR_DOMAIN_IA]" = "SLEW_FAST_8"