Darwin: Fixup TLV thunk functions during mapping #975

Job	Run time
macos-x86_64	6m 19s
linux-x86	3m 54s
android-arm (arm)	2m 19s
android-arm (arm64)	2m 42s
android-intel (x86)	1s
android-intel (x86_64)	1s
gir	2m 31s
freebsd-arm64	1m 40s
ios-arm64	1m 19s
linux-mips (mips, g++-mips-linux-gnu)	1s
linux-mips (mipsel, g++-mipsel-linux-gnu)	1s
linux-mips (mips64, g++-mips64-linux-gnuabi64)	1s
linux-mips (mips64el, g++-mips64el-linux-gnuabi64)	1s
linux-x86_64	3m 9s
qnx-armeabi	4m 40s
windows (amd64_x86)	9m 6s
windows (amd64)	7m 9s
	44m 54s

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