powerpc/book3e: remove #include <generated/utsrelease.h>

Commit 7ad4bd88 ("powerpc/book3e: get rid of #include <generated/compile.h>")
removed the usage of the define UTS_RELEASE but forgot to drop the
include.

utsrelease.h is potentially generated on each build. By removing the
unused include we can get rid of some spurious recompilations.

Fixes: 7ad4bd88 ("powerpc/book3e: get rid of #include <generated/compile.h>")
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Reviewed-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
[mpe: Fix typo in change log and add more explanation]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20221126051002.123199-2-linux@weissschuh.net

arch/powerpc/mm/nohash/kaslr_booke.c

@@ -19,7 +19,6 @@
 #include <asm/cacheflush.h>
 #include <asm/kdump.h>
 #include <mm/mmu_decl.h>
-#include <generated/utsrelease.h>
 
 struct regions {
 	unsigned long pa_start;