build: swap otool for (llvm-)objdump

Similar to libtool, (llvm-)otool only exists with a version suffix
on some systems (Ubuntu), which makes it annoying to use/find. Avoid
this, by switching to objdump. Which is a drop-in replacement.

This is related to #21778, and the switchover to using vanilla LLVM for
macOS.

depends/Makefile

@@ -233,7 +233,7 @@ $(host_prefix)/share/config.site : config.site.in $(host_prefix)/.stamp_$(final_
             -e 's|@RANLIB@|$(host_RANLIB)|' \
             -e 's|@NM@|$(host_NM)|' \
             -e 's|@STRIP@|$(host_STRIP)|' \
-            -e 's|@OTOOL@|$(host_OTOOL)|' \
+            -e 's|@OBJDUMP@|$(host_OBJDUMP)|' \
             -e 's|@DSYMUTIL@|$(host_DSYMUTIL)|' \
             -e 's|@build_os@|$(build_os)|' \
             -e 's|@host_os@|$(host_os)|' \