`add_library(simde)` fails

[louwers]

The following CMake line started failing.

add_library(simde INTERFACE IMPORTED GLOBAL)

CMake Error at vendor/fastpfor/cmake_modules/simde.cmake:9 (add_library):
add_library cannot create imported target "simde" because another target
with the same name already exists.
Call Stack (most recent call first):
vendor/fastpfor/CMakeLists.txt:47 (include)

Probably because simde now defines a library called simde. simd-everywhere/simde@4230ab6

Recommendations:

1. Pin simde to a specific commit.
2. Do not create simde library or do it with a unique name that does not conflict with simde.