module: make MODULE_SYMBOL_PREFIX into a CONFIG option

The next commit will require the use of MODULE_SYMBOL_PREFIX in
.tmp_exports-asm.S.  Currently it is mixed in with C structure
definitions in "asm/module.h".  Move the definition of this arch option
into Kconfig, so it can be easily accessed by any code.

This also lets modpost.c use the same definition.  Previously modpost
relied on a hardcoded list of architectures in mk_elfconfig.c.

A build test for blackfin, one of the two MODULE_SYMBOL_PREFIX archs,
showed the generated code was unchanged.  vmlinux was identical save
for build ids, and an apparently randomized suffix on a single "__key"
symbol in the kallsyms data).

Signed-off-by: Alan Jenkins <alan-jenkins@tuffmail.co.uk>
Acked-by: Mike Frysinger <vapier@gentoo.org> (blackfin)
CC: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

1 files changed, 4 insertions, 0 deletions

diff --git a/arch/h8300/Kconfig b/arch/h8300/Kconfig
index 9420648..53cc669 100644
--- a/arch/h8300/Kconfig
+++ b/arch/h8300/Kconfig
@@ -10,6 +10,10 @@ config H8300
 	default y
 	select HAVE_IDE
 
+config SYMBOL_PREFIX
+	string
+	default "_"
+
 config MMU
 	bool
 	default n