ebpf-code-legacy packages fetch the kernel-collector flavor selected by an inverted condition

The problem

packaging/cmake/Modules/NetdataEBPFLegacy.cmake decides which kernel-collector tarball flavor (glibc/musl/static) to fetch by testing BUILD_SHARED_LIBS:

if(DEFINED BUILD_SHARED_LIBS)
    if(NOT BUILD_SHARED_LIBS)
        set(need_static TRUE)
    endif()
endif()

(NetdataEBPFLegacy.cmake:14-18)

But CMakeLists.txt:26 sets that variable as a mirror of STATIC_BUILD:

set(BUILD_SHARED_LIBS "${STATIC_BUILD}")

So the selection is inverted relative to its apparent intent:

• a normal build (STATIC_BUILD=Off, i.e. every DEB and RPM) gets BUILD_SHARED_LIBS=OFF → need_static=TRUE → fetches netdata-kernel-collector-static-*.tar.xz;
• a static build (STATIC_BUILD=On) gets BUILD_SHARED_LIBS=ON → falls through to the libc detection → fetches the glibc/musl flavor.

The sibling module gets it right by testing the intent directly (NetdataLibBPF.cmake:35-37):

if(STATIC_BUILD)
  set(need_static TRUE)
endif()

Why this is a question and not just a fix

The DEB/RPM netdata-ebpf-code-legacy packages have shipped the static tarball's .o files for years, apparently without complaints — which suggests either flavor works at runtime, or that nobody exercising legacy eBPF hit a case where the flavor matters. Aligning the module with NetdataLibBPF.cmake changes the contents of shipped packages (DEB/RPM would start carrying the glibc flavor), so the intended flavor per artifact should be decided by the eBPF/packaging owners before any change:

1. Which flavor should DEB/RPM carry — glibc/musl per the build host, or static?
2. Which flavor should the static installer carry?
3. If the current shipped contents are actually correct, the fix is instead to make the condition say what it means (if(STATIC_BUILD) inverted, or an explicit flavor choice), so the next reader does not have to rediscover this.

Where

• packaging/cmake/Modules/NetdataEBPFLegacy.cmake:14-22
• CMakeLists.txt:26
• packaging/cmake/Modules/NetdataLibBPF.cmake:35-37 (the pattern to align with, whichever direction is chosen)