fix(freetype): Remove system lib dependencies (IEC-103)

[espressif2022]

Checklist

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Change description

1. Remove system lib dependencies: If the package required by find_package (such as BrotliDec, HarfBuzz) exists locally on Linux, the local lib will be used, causing compilation failure.
   -- Found BrotliDec: /usr/include (found version "1.0.9")
-- HarfBuzz (required): /usr/lib/x86_64-linux-gnu/libharfbuzz.so
/usr/include/stdlib.h:258:25: error: '_Float64x' is not supported on this target

[igrr]

@espressif2022 Could you please update the description, which issue does the PR fix? Is it a Linux-specific issue? I wonder why we didn't encounter it when this component gets built in CI.

[espressif2022]

@espressif2022 Could you please update the description, which issue does the PR fix? Is it a Linux-specific issue? I wonder why we didn't encounter it when this component gets built in CI.

This is related to the system version. For recently installed ubuntu, find_package will find the following system library problems, resulting in failed compilation, check that the package does exist locally.
If it does not exist in the local system, it can be compiled OK. I can't overwrite the option in sub cmake, so I want to ignore the system path here.
-- Found BrotliDec: /usr/include (found version "1.0.9")
-- HarfBuzz (required): /usr/lib/x86_64-linux-gnu/libharfbuzz.so

[igrr]

I see, thanks for explaining. I can reproduce the issue on macOS as well now, provided I install these libraries. I suppose we will need a more general solution since we can't possibly know all the possible include paths on all the systems.

I'm okay with merging this workaround first, though.

[igrr]

@espressif2022 I've opened #320 as a slightly more future-proof solution to the external dependencies issue.