Library bloat (with ZSTD_LIB_MINIFY=1) since v1.5.1

[hchunhui]

Describe the bug
Build zstd with ZSTD_LIB_MINIFY=1, the size of libzstd.a is increased since v1.5.1.

To Reproduce
Steps to reproduce the behavior:

git clone https://github.com/facebook/zstd
cd zstd

# build recent version (or v1.5.1/v1.5.2)
make -C lib ZSTD_LIB_MINIFY=1 libzstd.a
du -h lib/libzstd.a   # shows 604K

# build v1.5.0
make clean
git checkout v1.5.0
make -C lib ZSTD_LIB_MINIFY=1 libzstd.a
du -h lib/libzstd.a   # shows 328K

Expected behavior
The size of libzstd.a should be ~330K. The first bad commit is 8bf699a.

Desktop (please complete the following information):

• OS: Debian amd64
• Version: 11.2
• Compiler: gcc-10
• Flags: ZSTD_LIB_MINIFY=1
• Build system: Makefile

[terrelln]

Thanks for reporting the issue @hchunhui! Should be fixed after PR #3366 gets merged, and will be included in our next release.