powerpc/boot: Set LC_ALL=C in wrapper script

powerpc/boot: Set LC_ALL=C in wrapper script

While trying to build a simple Image for ACADIA platform, I got the
following error:

	  WRAP    arch/powerpc/boot/simpleImage.acadia
	INFO: Uncompressed kernel (size 0x6ae7d0) overlaps the address of the wrapper(0x400000)
	INFO: Fixing the link_address of wrapper to (0x700000)
	powerpc64-linux-gnu-ld : mode d'émulation non reconnu : -T
	Émulations prises en charge : elf64ppc elf32ppc elf32ppclinux elf32ppcsim elf64lppc elf32lppc elf32lppclinux elf32lppcsim
	make[1]: *** [arch/powerpc/boot/Makefile:424 : arch/powerpc/boot/simpleImage.acadia] Erreur 1
	make: *** [arch/powerpc/Makefile:285 : simpleImage.acadia] Erreur 2

Trying again with V=1 shows the following command

	powerpc64-linux-gnu-ld -m -T arch/powerpc/boot/zImage.lds -Ttext 0x700000 --no-dynamic-linker -o arch/powerpc/boot/simpleImage.acadia -Map wrapper.map arch/powerpc/boot/fixed-head.o arch/powerpc/boot/simpleboot.o ./zImage.3278022.o arch/powerpc/boot/wrapper.a

The argument of '-m' is missing.

This is due to the wrapper script calling 'objdump -p vmlinux' and
looking for 'file format', whereas the output of objdump is:

	vmlinux:     format de fichier elf32-powerpc

	En-tête de programme:
	    LOAD off    0x00010000 vaddr 0xc0000000 paddr 0x00000000 align 2**16
	         filesz 0x0069e1d4 memsz 0x006c128c flags rwx
	    NOTE off    0x0064591c vaddr 0xc063591c paddr 0x0063591c align 2**2
	         filesz 0x00000054 memsz 0x00000054 flags ---

Add LC_ALL=C at the beginning of the wrapper script in order to get the
output expected by the script:

	vmlinux:     file format elf32-powerpc

	Program Header:
	    LOAD off    0x00010000 vaddr 0xc0000000 paddr 0x00000000 align 2**16
	         filesz 0x0069e1d4 memsz 0x006c128c flags rwx
	    NOTE off    0x0064591c vaddr 0xc063591c paddr 0x0063591c align 2**2
	         filesz 0x00000054 memsz 0x00000054 flags ---

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Acked-by: Segher Boessenkool <segher@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/a9ff3bc98035f63b122c051f02dc47c7aed10430.1635256089.git.christophe.leroy@csgroup.eu