fixup bbr v3: remove references to v1 and v2

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Tested: <multi line explanation of how the code was tested>

Effort: <Your effort group>
Google-Bug-Id: <buganizer-id>
Change-Id: I3733e13515bd90b758f2f107556989c87af91dfb

net/ipv4/tcp_bbr.c

@@ -232,7 +232,7 @@ enum bbr_pacing_gain_phase {
 	BBR_BW_PROBE_UP		= 0,  /* push up inflight to probe for bw/vol */
 	BBR_BW_PROBE_DOWN	= 1,  /* drain excess inflight from the queue */
 	BBR_BW_PROBE_CRUISE	= 2,  /* use pipe, w/ headroom in queue/pipe */
-	BBR_BW_PROBE_REFILL	= 3,  /* v2: refill the pipe again to 100% */
+	BBR_BW_PROBE_REFILL	= 3,  /* try to refill the pipe again to 100% */
 };
 
 /* Try to keep at least this many packets in flight, if things go smoothly. For
@@ -1164,10 +1164,9 @@ static void bbr_probe_inflight_hi_upward(struct sock *sk,
 		bbr_raise_inflight_hi_slope(sk);
 }
 
-/* Does loss/ECN rate for this sample say inflight is "too high"?
- * This is used by both the bbr_check_loss_too_high_in_startup() function,
- * which can be used in either v1 or v2, and the PROBE_UP phase of v2, which
- * uses it to notice when loss/ECN rates suggest inflight is too high.
+/* Does loss/ECN rate for this sample suggest inflight is "too high"? This is
+ * used both in STARTUP and BBR_BW_PROBE_UP, to notice when loss/ECN rates
+ * suggest the volume of in-flight data is too high.
  */
 static bool bbr_is_inflight_too_high(const struct sock *sk,
 				      const struct rate_sample *rs)