OhmSpice ngspice corresponding source

Upstream commit: 4feeb94b12a2529f14f9bd7847f7253d704990af
Upstream repository: https://git.code.sf.net/p/ngspice/ngspice

This archive contains the complete ngspice source tree after applying the
OhmSpice patches used for the distributed WebAssembly build. The
ohmspice-build directory also contains the exact patch set, source pin,
native bridge, and build script. Build prerequisites and commands are in
build-ngspice-wasm.mjs and the upstream build files.

See COPYING and file headers for the applicable licenses.
