Fixed warning about strict prototypes for cpu_check_features.

[nmoinvaz]

This warning happens for every time cpu_features.h is included:

cpu_features.h:22:31: warning: this function declaration is not a prototype [-Wstrict-prototypes]
extern void cpu_check_features();
                              ^
                               void

In cpu_features.c it is defined as:

Z_INTERNAL void cpu_check_features(void)

[codecov]

Codecov Report

Merging #1265 (b4aa437) into develop (4422a6b) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff            @@
##           develop    #1265   +/-   ##
========================================
  Coverage    87.34%   87.34%           
========================================
  Files          115      115           
  Lines        10202    10202           
  Branches      2574     2574           
========================================
  Hits          8911     8911           
- Misses         962      963    +1     
+ Partials       329      328    -1     

Flag	Coverage Δ
macos_clang	33.33% <ø> (ø)
macos_gcc	74.95% <ø> (ø)
ubuntu_clang	87.42% <ø> (ø)
ubuntu_clang_debug	86.15% <ø> (-0.82%)	⬇️
ubuntu_clang_inflate_allow_invalid_dist	87.12% <ø> (ø)
ubuntu_clang_inflate_strict	87.37% <ø> (ø)
ubuntu_clang_mmap	87.56% <ø> (ø)
ubuntu_clang_pigz	40.95% <ø> (ø)
ubuntu_clang_pigz_no_optim	41.14% <ø> (ø)
ubuntu_clang_pigz_no_threads	40.53% <ø> (ø)
ubuntu_clang_reduced_mem	86.97% <ø> (-0.86%)	⬇️
ubuntu_gcc	77.01% <ø> (ø)
ubuntu_gcc_aarch64	77.31% <ø> (ø)
ubuntu_gcc_aarch64_compat_no_opt	75.36% <ø> (ø)
ubuntu_gcc_aarch64_no_acle	76.20% <ø> (ø)
ubuntu_gcc_aarch64_no_neon	76.09% <ø> (ø)
ubuntu_gcc_armhf	77.32% <ø> (ø)
ubuntu_gcc_armhf_compat_no_opt	75.28% <ø> (ø)
ubuntu_gcc_armhf_no_acle	77.34% <ø> (ø)
ubuntu_gcc_armhf_no_neon	77.10% <ø> (ø)
ubuntu_gcc_armsf	77.19% <ø> (ø)
ubuntu_gcc_armsf_compat_no_opt	74.95% <ø> (ø)
ubuntu_gcc_benchmark	75.00% <ø> (+0.37%)	⬆️
ubuntu_gcc_compat_no_opt	76.50% <ø> (ø)
ubuntu_gcc_compat_sprefix	75.10% <ø> (ø)
ubuntu_gcc_m32	74.84% <ø> (ø)
ubuntu_gcc_mingw_i686	0.00% <ø> (ø)
ubuntu_gcc_mingw_x86_64	0.00% <ø> (ø)
ubuntu_gcc_no_avx2	76.66% <ø> (ø)
ubuntu_gcc_no_ctz	74.77% <ø> (ø)
ubuntu_gcc_no_ctzll	74.80% <ø> (ø)
ubuntu_gcc_no_pclmulqdq	75.44% <ø> (ø)
ubuntu_gcc_no_sse2	76.72% <ø> (ø)
ubuntu_gcc_no_sse4	76.26% <ø> (ø)
ubuntu_gcc_o1	75.97% <ø> (ø)
ubuntu_gcc_osb	∅ <ø> (∅)
ubuntu_gcc_pigz	38.90% <ø> (ø)
ubuntu_gcc_pigz_aarch64	39.35% <ø> (ø)
ubuntu_gcc_ppc	73.82% <ø> (ø)
ubuntu_gcc_ppc64	74.56% <ø> (ø)
ubuntu_gcc_ppc64le	74.54% <ø> (ø)
ubuntu_gcc_ppc_no_power8	74.74% <ø> (ø)
ubuntu_gcc_s390x	74.73% <ø> (ø)
ubuntu_gcc_s390x_dfltcc	72.09% <ø> (ø)
ubuntu_gcc_s390x_dfltcc_compat	73.63% <ø> (ø)
ubuntu_gcc_s390x_no_crc32	74.51% <ø> (ø)
ubuntu_gcc_sparc64	74.62% <ø> (ø)
ubuntu_gcc_sprefix	74.89% <ø> (ø)
win64_gcc	73.96% <ø> (ø)
win64_gcc_compat_no_opt	73.98% <ø> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
uncompr.c	91.30% <0.00%> (ø)

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[mtl1979]

I don't like "void" as sole parameter for function, but this is about strict compliance and C is a lot stricter than C++ when it comes to prototypes of functions.