libstdc++: Update Solaris baselines for GCC 15.1

libstdc++: Update Solaris baselines for GCC 15.1

This patch updates the Solaris libstdc++ baselines for GCC 15.1.

Tested on i386-pc-solaris2.11 and sparc-sun-solaris2.11 on both the
gcc-15 branch and trunk.

2025-02-11  Rainer Orth  <ro@CeBiTec.Uni-Bielefeld.DE>

	libstdc++-v3:
	* config/abi/post/i386-solaris/baseline_symbols.txt: Regenerate.
	* config/abi/post/i386-solaris/amd64/baseline_symbols.txt:
	Likewise.
	* config/abi/post/sparc-solaris/baseline_symbols.txt: Likewise.
	* config/abi/post/sparc-solaris/sparcv9/baseline_symbols.txt:
	Likewise.

(cherry picked from commit 0c8f5e9f7a3cf5cb853ae485796021653ef4be7c)