soc/intel/alderlake: Add support for I2C6 and I2C7

As per the EDS revision 1.3 add support for I2C6 and I2C7.

Signed-off-by: Varshit B Pandya <varshit.b.pandya@intel.com>
Change-Id: Id918d55e48b91993af9de8381995917aef55edc9
Reviewed-on: https://review.coreboot.org/c/coreboot/+/55996
Reviewed-by: Tim Wawrzynczak <twawrzynczak@chromium.org>
Reviewed-by: Maulik V Vaghela <maulik.v.vaghela@intel.com>
Reviewed-by: Paul Menzel <paulepanter@mailbox.org>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/soc/intel/alderlake/Kconfig

@@ -223,7 +223,7 @@ config SOC_INTEL_COMMON_BLOCK_GSPI_MAX
 
 config SOC_INTEL_I2C_DEV_MAX
 	int
-	default 6
+	default 8
 
 config SOC_INTEL_UART_DEV_MAX
 	int