Fixes backtrace is missing in libubacktrace.so. Broken in this upstream commit 6b2250a1a39362abe53e78a45897caecf65ec73f

--- libubacktrace/Makefile.in
+++ libubacktrace/Makefile.in
@@ -26,12 +26,12 @@
 
 libubacktrace_SRC-y :=
 libubacktrace_SRC-$(UCLIBC_HAS_BACKTRACE) := backtracesyms.c backtracesymsfd.c
-libubacktrace_SRC_SHARED-$(UCLIBC_HAS_BACKTRACE) := backtrace.c
+libubacktrace_SHARED_SRC-$(UCLIBC_HAS_BACKTRACE) := backtrace.c
 
 # remove generic sources, if arch specific version is present
 ifneq ($(strip $(libubacktrace_ARCH_SRC-y)),)
 libubacktrace_SRC-y := $(filter-out $(notdir $(libubacktrace_ARCH_SRC-y)),$(libubacktrace_SRC-y))
-libubacktrace_SRC_SHARED-y := $(filter-out $(notdir $(libubacktrace_ARCH_SRC-y)),$(libubacktrace_SRC_SHARED-y))
+libubacktrace_SHARED_SRC-y := $(filter-out $(notdir $(libubacktrace_ARCH_SRC-y)),$(libubacktrace_SHARED_SRC-y))
 endif
 
 # -fasynchronous-unwind-tables is required for backtrace to work using dwarf2
@@ -46,9 +46,9 @@
 libubacktrace_OBJS := $(patsubst $(libubacktrace_DIR)/%.c,$(libubacktrace_OUT)/%.o,$(libubacktrace_SRCS))
 
 libubacktrace_SHARED_SRCS := $(patsubst %.c,$(libubacktrace_DIR)/%.c,$(libubacktrace_SHARED_SRC-y))
-libubacktrace_SHARED_OBJS := $(patsubst $(libubacktrace_DIR)/%.c,$(libubacktrace_OUT)/%.s,$(libubacktrace_SHARED_SRCS))
+libubacktrace_SHARED_OBJS := $(patsubst $(libubacktrace_DIR)/%.c,$(libubacktrace_OUT)/%.o,$(libubacktrace_SHARED_SRCS))
 
-libubacktrace-shared-y	:= $(libubacktrace_SHARED_OBJS:.os=.oS)
+libubacktrace-shared-y	:= $(libubacktrace_SHARED_OBJS:.o=.oS)
 libubacktrace-static-y	:= $(libubacktrace_SHARED_OBJS)
 
 ifeq ($(DOPIC),y)