No arm source refers to SOFTFLOAT.

So why bother #defining it?

Bug: 18160821

(cherry picked from commit b1a6c319c40674d71e30313040d3b33b8bddf24b)

Change-Id: I9cd9c144ba7071fddda12fa16d1232ad861b66be
diff --git a/libc/arch-arm/arm.mk b/libc/arch-arm/arm.mk
index b1edfcc..8c5e681 100644
--- a/libc/arch-arm/arm.mk
+++ b/libc/arch-arm/arm.mk
@@ -44,8 +44,6 @@
 #    bionic/__strcpy_chk.cpp \
 #    bionic/__strcat_chk.cpp \
 
-libc_common_cflags_arm := -DSOFTFLOAT
-
 ##########################################
 ### CPU specific source files
 libc_bionic_src_files_arm += \