Build[mqbs_filesystemutil.cpp]: Solaris GCC fix (#839)

Signed-off-by: Evgenii Malygin <emalygin@bloomberg.net>

Author: 678098

src/groups/mqb/mqbs/mqbs_filesystemutil.cpp

@@ -178,7 +178,7 @@
 
 // GCC on Solaris 10 cannot find madvise declaration. Providing one explicitly.
 #if defined(BSLS_PLATFORM_OS_SOLARIS) && defined(BSLS_PLATFORM_CMP_GNU)
-extern "C" int madvise(caddr_t, size_t, int);
+extern "C" int madvise(void*, size_t, int);
 #endif
 
 namespace BloombergLP {