cmd/compile: update default PGO profile

Since last time the default.pgo profile is collected, there has
been a lot of development in the compiler. It's time to refresh
the compiler's PGO profile.

Profile collected by running the cmd/compile/profile.sh script on
the gotip-linux-amd64_c2s16-perf_vs_release gomote.

There is a slight improvement on benchmark results. On Linux/AMD64,

         │  nopgo.txt  │              old.txt               │              new.txt               │
         │   sec/op    │   sec/op     vs base               │   sec/op     vs base               │
Template   142.5m ± 1%   140.8m ± 1%  -1.23% (p=0.017 n=20)   141.3m ± 1%  -0.87% (p=0.011 n=20)
Unicode    122.7m ± 1%   116.6m ± 1%  -4.95% (p=0.000 n=20)   114.9m ± 1%  -6.28% (p=0.000 n=20)
GoTypes    889.1m ± 0%   872.3m ± 1%  -1.89% (p=0.000 n=20)   864.9m ± 1%  -2.73% (p=0.000 n=20)
Compiler   161.0m ± 1%   151.9m ± 1%  -5.65% (p=0.000 n=20)   151.5m ± 1%  -5.90% (p=0.000 n=20)
SSA         8.626 ± 0%    8.337 ± 0%  -3.34% (p=0.000 n=20)    8.294 ± 0%  -3.85% (p=0.000 n=20)
Flate      148.1m ± 2%   145.3m ± 1%  -1.91% (p=0.005 n=20)   145.8m ± 2%  -1.56% (p=0.026 n=20)
GoParser   160.7m ± 2%   160.0m ± 1%       ~ (p=0.174 n=20)   158.7m ± 1%  -1.23% (p=0.001 n=20)
Reflect    389.9m ± 1%   383.9m ± 1%  -1.55% (p=0.000 n=20)   382.2m ± 1%  -1.97% (p=0.000 n=20)
Tar        159.6m ± 1%   157.2m ± 1%  -1.48% (p=0.000 n=20)   157.7m ± 1%  -1.18% (p=0.015 n=20)
XML        186.2m ± 2%   183.4m ± 2%       ~ (p=0.056 n=20)   182.4m ± 1%  -2.03% (p=0.001 n=20)
geomean    300.2m        293.0m       -2.41%                  291.9m       -2.78%

For #60234.

Change-Id: I4101115f9c8005c3180db7a1600c0bc81bef7d5c
Reviewed-on: https://go-review.googlesource.com/c/go/+/792120
LUCI-TryBot-Result: golang-scoped@luci-project-accounts.iam.gserviceaccount.com <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: David Chase <drchase@google.com>
SLSA-Policy-Verified: SLSA Policy Verification Service <devtools-gerritcodereview-exitgate@google.com>
diff --git a/src/cmd/compile/default.pgo b/src/cmd/compile/default.pgo
index 2c25887..06e63b4 100644
--- a/src/cmd/compile/default.pgo
+++ b/src/cmd/compile/default.pgo
Binary files differ