fix documentation of mtu field in interconnect attachments resource (#14053) (#22977)

[upstream:01b8438246bfcdb028ab470d48098f6075422899]

Signed-off-by: Modular Magician <[email protected]>

Author: modular-magician

google/services/compute/resource_compute_interconnect_attachment.go

@@ -215,8 +215,8 @@ Please refer to the field 'effective_labels' for all of the labels present on th
 				Type:     schema.TypeString,
 				Computed: true,
 				Optional: true,
-				Description: `Maximum Transmission Unit (MTU), in bytes, of packets passing through
-this interconnect attachment. Currently, only 1440 and 1500 are allowed. If not specified, the value will default to 1440.`,
+				Description: `Maximum Transmission Unit (MTU), in bytes, of packets passing through this interconnect attachment.
+Valid values are 1440, 1460, 1500, and 8896. If not specified, the value will default to 1440.`,
 			},
 			"region": {
 				Type:             schema.TypeString,

website/docs/r/compute_interconnect_attachment.html.markdown

@@ -148,8 +148,8 @@ The following arguments are supported:
 
 * `mtu` -
   (Optional)
-  Maximum Transmission Unit (MTU), in bytes, of packets passing through
-  this interconnect attachment. Currently, only 1440 and 1500 are allowed. If not specified, the value will default to 1440.
+  Maximum Transmission Unit (MTU), in bytes, of packets passing through this interconnect attachment.
+  Valid values are 1440, 1460, 1500, and 8896. If not specified, the value will default to 1440.
 
 * `bandwidth` -
   (Optional)