cmake: document `-D` and env build options

Extend `INSTALL-CMAKE` document with the list of available options,
a short description and default values.

The list may not be 100% c

cmake: document `-D` and env build options

Extend `INSTALL-CMAKE` document with the list of available options,
a short description and default values.

The list may not be 100% complete.

There are no component boundaries in CMake, so the line is blurry
between curl options, CMake options, CMake Find modules options.
I included certain CMake options that seemed useful, and/or have
dedicated use withing curl's CMake source. But, all CMake built-in
options are usable, as documented upstream in CMake.

The naming of the options has a heritage and the inconsistencies with
it, including a lack of clear namespace. This may be subject to future
updates, also after figuring out which name has special meaning within
CMake and/or CMake projects out of unwritten convention or something
more tangible.

CMake allows to initialize any internal variable via `-D`. This may be
useful to pre-initialize/override feature check results. The list
doesn't contain these, and they remain officially undocumented.

Also:
- make adjustments to keep the spellchecker happy.
- retrofit description changes to the cmake sources.
- stop documenting deprecated `Find*` variables.

Reported-by: Daniel Stenberg
Fixes https://github.com/curl/curl/discussions/14885
Closes #15388

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cmake: add native `pkg-config` detection for mbedTLS, MSH3, Quiche, Rustls, wolfSSL

Also:
- detect and add required system libraries for Rustls on macOS and
non-Windows.
- add

cmake: add native `pkg-config` detection for mbedTLS, MSH3, Quiche, Rustls, wolfSSL

Also:
- detect and add required system libraries for Rustls on macOS and
non-Windows.
- add Linux CMake jobs for the touched dependencies.
Caveats:
- MSH3 generates a broken `libmsh3.pc`, so needs manual config.
Upstream PR: https://github.com/nibanks/msh3/pull/225
- Rustls `.pc` file missing, so needs manual config.

An internal change worthy of mention is that we are using the lib path
and name information returned by `pkg-config` as-is. Meaning the libname
doesn't include the full path, like it's usual with native cmake
detection. The path comes separately and needs to be rolled separately.
For this we add it to targets via `link_directories()`. We also keep tab
of them in `CURL_LIBDIRS` and use that in `libcurl.pc`. Feature checks
also need to receive these paths. CMake doesn't offer
a `CMAKE_REQUIRED_*` variable for this purpose, only
a `CMAKE_REQUIRED_LINK_OPTIONS` accepting raw linker flags. Add a macro
to convert a list of paths to linker options to solve it. wolfSSL
requires this for now.

Closes #15193

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cmake: rename Find modules

- `FindCARES` -> `FindCares`
- `FindLibPSL` -> `FindLibpsl`
- `FindLibSSH2` -> `FindLibssh2`
- `FindQUICHE` -> `FindQuiche`
- `Findrustls` ->

cmake: rename Find modules

- `FindCARES` -> `FindCares`
- `FindLibPSL` -> `FindLibpsl`
- `FindLibSSH2` -> `FindLibssh2`
- `FindQUICHE` -> `FindQuiche`
- `Findrustls` -> `FindRustls`

Our convention for naming Find modules (the part after the `Find`
prefix, also called as 'package name') is:

Always start with uppercase. Follow with lowercase, unless there is
a clear preference for a stylized name. E.g. the project itself uses it
that way with a matching `<Name>Config.cmake` file, or we use it that
way elsewhere, or the name is an acronym.

Ref: #14580

Closes #14601

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