add build note to assembler sources

When distros use the annobin compiler plugin [1], they have complete overview
what compiler flags were used for compilation and they are able to perform
security checks on the produced binaries. Compiling assembler source can't
provide this kind of information by default, so we need the explicit
-Wa,--generate-missing-build-notes=yes option during build. When the option is
missing, then the annocheck tool reports "GAPS" in the resulting binary.

[1] https://fedoraproject.org/wiki/Changes/Annobin

Signed-off-by: Dan Horák <[email protected]>

src/Makefile.am

@@ -8,7 +8,7 @@ lib_LTLIBRARIES = libica.la
 
 libica_la_CFLAGS = ${AM_CFLAGS} -I${srcdir}/include -I${srcdir}/../include \
 		   -fvisibility=hidden
-libica_la_CCASFLAGS = ${AM_CFLAGS}
+libica_la_CCASFLAGS = ${AM_CFLAGS} -Wa,--generate-missing-build-notes=yes
 libica_la_LIBADD = @LIBS@ -lrt -lcrypto
 libica_la_LDFLAGS = -Wl,--version-script=${srcdir}/../libica.map \
 		    -version-number ${VERSION}