Moves several clothing-specific flags from /atom to their proper type

code/modules/clothing/head/hardhat.dm

@@ -46,7 +46,7 @@
 	item_color = "red"
 	dog_fashion = null
 	name = "firefighter helmet"
-	flags_1 = STOPSPRESSUREDMAGE_1
+	clothing_flags = STOPSPRESSUREDAMAGE
 	heat_protection = HEAD
 	max_heat_protection_temperature = FIRE_HELM_MAX_TEMP_PROTECT
 	cold_protection = HEAD
@@ -56,7 +56,7 @@
 	icon_state = "hardhat0_white"
 	item_state = "hardhat0_white"
 	item_color = "white"
-	flags_1 = STOPSPRESSUREDMAGE_1
+	clothing_flags = STOPSPRESSUREDAMAGE
 	heat_protection = HEAD
 	max_heat_protection_temperature = FIRE_HELM_MAX_TEMP_PROTECT
 	cold_protection = HEAD
@@ -76,7 +76,7 @@
 	dog_fashion = null
 	name = "atmospheric technician's firefighting helmet"
 	desc = "A firefighter's helmet, able to keep the user cool in any situation."
-	flags_1 = STOPSPRESSUREDMAGE_1 | THICKMATERIAL_1
+	clothing_flags = STOPSPRESSUREDAMAGE | THICKMATERIAL | BLOCK_GAS_SMOKE_EFFECT
 	flags_inv = HIDEMASK|HIDEEARS|HIDEEYES|HIDEFACE|HIDEHAIR|HIDEFACIALHAIR
 	heat_protection = HEAD
 	max_heat_protection_temperature = FIRE_IMMUNITY_HELM_MAX_TEMP_PROTECT

code/modules/clothing/head/helmet.dm

@@ -122,7 +122,7 @@
 	min_cold_protection_temperature = SPACE_HELM_MIN_TEMP_PROTECT
 	heat_protection = HEAD
 	max_heat_protection_temperature = SPACE_HELM_MAX_TEMP_PROTECT
-	flags_1 = STOPSPRESSUREDMAGE_1
+	clothing_flags = STOPSPRESSUREDAMAGE
 	strip_delay = 80
 	dog_fashion = null