internal/lsp/cache: don't trim types.Info with staticcheck enabled
internal/lsp/cache: don't trim types.Info with staticcheck enabled

As predicted in CL 308730, there are some analyzers that need this: all
of staticcheck. (I probably should've seen that coming.) For now, don't
do the trimming when staticcheck is on. Since staticcheck ~doubles
memory footprint, those users probably don't care much.

Change-Id: I7cfd96b3654e3617d28d62015928a45a85407d13
Reviewed-on: https://go-review.googlesource.com/c/tools/+/311376
Trust: Heschi Kreinick <e89ab2b172855aa0ad01c40c4d8a3535a61ac68a@google.com>
Run-TryBot: Heschi Kreinick <e89ab2b172855aa0ad01c40c4d8a3535a61ac68a@google.com>
gopls-CI: kokoro <2ac7b1f3fa578934c95181d4272be0d3bca00121@google.com>
TryBot-Result: Go Bot <66cb808b70d30c07676d5e946fee83fd561249e5@golang.org>
Reviewed-by: Robert Findley <9179eee875d1ee628c37fb47d7e749e855ffd21f@google.com>

golang/tools,golang/tools,golang/tools,golang/tools,golang/tools