package/libbsd: fix display of Config.in comment

Commit e13855c4 wrongly added
depends on BR2_TOOLCHAIN_USES_UCLIBC && !BR2_USE_MMU
to display the comment "libbsd needs a toolchain w/ threads, wchar"
The same error has also been made for minizip.

To fix this issue, move dependency
!(BR2_TOOLCHAIN_USES_UCLIBC && !BR2_USE_MMU) under
BR2_PACKAGE_LIBBSD_ARCH_SUPPORTS.

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>