sparc32: Use generic cmpdi2/ucmpdi2 variants

Use the generic variants - the implementation is the same.
As a nice side-effect fix the following warnings:

cmpdi2.c: warning: no previous prototype for '__cmpdi2' [-Wmissing-prototypes]
ucmpdi2.c: warning: no previous prototype for '__ucmpdi2' [-Wmissing-prototypes]
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Fixes: 0fcb7085 ("Makefile.extrawarn: turn on missing-prototypes globally")
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org> # build-tested
Reviewed-by: Maciej W. Rozycki <macro@orcam.me.uk>
Tested-by: Maciej W. Rozycki <macro@orcam.me.uk> # build-tested
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Andreas Larsson <andreas@gaisler.com>
Reviewed-by: Andreas Larsson <andreas@gaisler.com>
Tested-by: Andreas Larsson <andreas@gaisler.com>
Signed-off-by: Andreas Larsson <andreas@gaisler.com>
Link: https://lore.kernel.org/r/20240224-sam-fix-sparc32-all-builds-v2-1-1f186603c5c4@ravnborg.org

arch/sparc/Kconfig

@@ -57,6 +57,8 @@ config SPARC32
 	select CLZ_TAB
 	select DMA_DIRECT_REMAP
 	select GENERIC_ATOMIC64
+	select GENERIC_LIB_CMPDI2
+	select GENERIC_LIB_UCMPDI2
 	select HAVE_UID16
 	select LOCK_MM_AND_FIND_VMA
 	select OLD_SIGACTION

arch/sparc/lib/Makefile

@@ -14,7 +14,7 @@ lib-$(CONFIG_SPARC32) += divdi3.o udivdi3.o
 lib-$(CONFIG_SPARC32) += copy_user.o locks.o
 lib-$(CONFIG_SPARC64) += atomic_64.o
 lib-$(CONFIG_SPARC32) += lshrdi3.o ashldi3.o
-lib-$(CONFIG_SPARC32) += muldi3.o bitext.o cmpdi2.o
+lib-$(CONFIG_SPARC32) += muldi3.o bitext.o
 lib-$(CONFIG_SPARC64) += multi3.o
 lib-$(CONFIG_SPARC64) += fls.o
 lib-$(CONFIG_SPARC64) += fls64.o
@@ -51,5 +51,5 @@ lib-$(CONFIG_SPARC64) += copy_in_user.o memmove.o
 lib-$(CONFIG_SPARC64) += mcount.o ipcsum.o xor.o hweight.o ffs.o
 
 obj-$(CONFIG_SPARC64) += iomap.o
-obj-$(CONFIG_SPARC32) += atomic32.o ucmpdi2.o
+obj-$(CONFIG_SPARC32) += atomic32.o
 obj-$(CONFIG_SPARC64) += PeeCeeI.o

arch/sparc/lib/cmpdi2.c

-// SPDX-License-Identifier: GPL-2.0
-#include <linux/module.h>
-
-#include "libgcc.h"
-
-word_type __cmpdi2(long long a, long long b)
-{
-	const DWunion au = {
-		.ll = a
-	};
-	const DWunion bu = {
-		.ll = b
-	};
-
-	if (au.s.high < bu.s.high)
-		return 0;
-	else if (au.s.high > bu.s.high)
-		return 2;
-
-	if ((unsigned int) au.s.low < (unsigned int) bu.s.low)
-		return 0;
-	else if ((unsigned int) au.s.low > (unsigned int) bu.s.low)
-		return 2;
-
-	return 1;
-}
-
-EXPORT_SYMBOL(__cmpdi2);

arch/sparc/lib/ucmpdi2.c

-// SPDX-License-Identifier: GPL-2.0
-#include <linux/module.h>
-#include "libgcc.h"
-
-word_type __ucmpdi2(unsigned long long a, unsigned long long b)
-{
-	const DWunion au = {.ll = a};
-	const DWunion bu = {.ll = b};
-
-	if ((unsigned int) au.s.high < (unsigned int) bu.s.high)
-		return 0;
-	else if ((unsigned int) au.s.high > (unsigned int) bu.s.high)
-		return 2;
-	if ((unsigned int) au.s.low < (unsigned int) bu.s.low)
-		return 0;
-	else if ((unsigned int) au.s.low > (unsigned int) bu.s.low)
-		return 2;
-	return 1;
-}
-EXPORT_SYMBOL(__ucmpdi2);