[Memprof] Reduce test binary sizes for memprof tests. (#97114)

PR 94264 had substantial increase in test binary size. This was due to
building LLVM and compiler-rt with GCC, implicitly causing the

[Memprof] Reduce test binary sizes for memprof tests. (#97114)

PR 94264 had substantial increase in test binary size. This was due to
building LLVM and compiler-rt with GCC, implicitly causing the runtimes
to be built with full debuginfo. Rebuilding LLVM with
`-DCMAKE_CXX_COMPILER=/usr/bin/clang++` and regenerating .exe files with
script `update_memprof_inputs.sh` avoids this increase in test binary
size.

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[Memprof] Adds the option to collect AccessCountHistograms for memprof. (#94264)

Adds compile time flag -mllvm -memprof-histogram and runtime flag
histogram=true|false to turn Histogram collection

[Memprof] Adds the option to collect AccessCountHistograms for memprof. (#94264)

Adds compile time flag -mllvm -memprof-histogram and runtime flag
histogram=true|false to turn Histogram collection on and off. The
-memprof-histogram flag relies on -memprof-use-callbacks=true to work.

Updates shadow mapping logic in histogram mode from having one 8 byte
counter for 64 bytes, to 1 byte for 8 bytes, capped at 255. Only
supports this granularity as of now.

Updates the RawMemprofReader and serializing MemoryInfoBlocks to binary
format, including changing to a new version of the raw binary format
from version 3 to version 4.

Updates creating MemoryInfoBlocks with and without Histograms. When two
MemoryInfoBlocks are merged, AccessCounts are summed up and the shorter
Histogram is removed.

Adds a memprof_histogram test case.

Initial commit for adding AccessCountHistograms up until RawProfile for
memprof

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