[Mellanox] Update FW version to 2008.3218 (sonic-net#8079)

Update FW version to 2008.3218, fixing the following issues:
- 50G/100G links that are operationally down before warm-reboot are not coming up after warm-reboot
- 50G/100G links with admin shut / no shut commands are not coming up after warm-reboot

Signed-off-by: Dror Prital <drorp@nvidia.com>

platform/mellanox/fw.mk

@@ -11,17 +11,17 @@ else
 FW_FROM_URL = n
 endif
 
-MLNX_SPC_FW_VERSION = 13.2008.3216
+MLNX_SPC_FW_VERSION = 13.2008.3218
 MLNX_SPC_FW_FILE = fw-SPC-rel-$(subst .,_,$(MLNX_SPC_FW_VERSION))-EVB.mfa
 $(MLNX_SPC_FW_FILE)_PATH = $(MLNX_FW_BASE_PATH)
 $(MLNX_SPC_FW_FILE)_URL = $(MLNX_FW_BASE_URL)/$(MLNX_SPC_FW_FILE)
 
-MLNX_SPC2_FW_VERSION = 29.2008.3216
+MLNX_SPC2_FW_VERSION = 29.2008.3218
 MLNX_SPC2_FW_FILE = fw-SPC2-rel-$(subst .,_,$(MLNX_SPC2_FW_VERSION))-EVB.mfa
 $(MLNX_SPC2_FW_FILE)_PATH = $(MLNX_FW_BASE_PATH)
 $(MLNX_SPC2_FW_FILE)_URL = $(MLNX_FW_BASE_URL)/$(MLNX_SPC2_FW_FILE)
 
-MLNX_SPC3_FW_VERSION = 30.2008.3216
+MLNX_SPC3_FW_VERSION = 30.2008.3218
 MLNX_SPC3_FW_FILE = fw-SPC3-rel-$(subst .,_,$(MLNX_SPC3_FW_VERSION))-EVB.mfa
 $(MLNX_SPC3_FW_FILE)_PATH = $(MLNX_FW_BASE_PATH)
 $(MLNX_SPC3_FW_FILE)_URL = $(MLNX_FW_BASE_URL)/$(MLNX_SPC3_FW_FILE)