When booted from stick, EFI would use GPT partition and our root
device detection algortihm depends on GRUB's ability to see the same
partitions. Hence include msdos and gpt partmap modules on EFI even when
they're not needed to access root filesystem.
On Mac rescue image is booted from HFS+ partition, so bootpath looks like
/ACPI(a0341d0,0)/PCI(1,1f)/ATAPI(0,0,0)/HD(3,5d1,ca3,0000000000000000,20,0)/EndEntire
grub fails to find device for this path because it cannot scan partition
table. The simplest fix is to add part_apple by default.
Split single string in help message into several strings used before in shell
grub-mkrescue to minimize changes to existing translations.
Reported by Benno Schulenberg
Add grub_util_disable_fd_syncs call to turn grub_util_fd_sync calls into
no-ops, and use it in programs that copy files but do not need to take
special care to sync writes (grub-mknetdir, grub-rescue,
grub-mkstandalone).
On my laptop, this reduces partmap_test's runtime from 1236 seconds to
204 seconds.
the function of these files exceeds what can be sanely handled in shell
in posix-comaptible way. Also writing it in C extends the functionality
to non-UNIX-like OS and minimal environments.