[Buildroot] [git commit branch/next] package/xml-security-c: fix syntax error

[Thomas Petazzoni]

commit: https://git.buildroot.net/buildroot/commit/?id=209e580219640fd0a12e6af15e4a611f4660fdba
branch: https://git.buildroot.net/buildroot/commit/?id=refs/heads/next

Add missed backslash to fix such error:
package/xml-security-c/Config.in:16: syntax error
package/xml-security-c/Config.in:15: invalid option
package/xml-security-c/Config.in:15:warning: ignoring unsupported character '!'
package/xml-security-c/Config.in:16: unknown option "BR2_TOOLCHAIN_GCC_AT_LEAST_4_7"

Fixes: bbda38afbbfa ("package/xml-security-c: new package")
Signed-off-by: Maxim Kochetkov <fido_max at inbox.ru>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni at bootlin.com>
---
 package/xml-security-c/Config.in | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package/xml-security-c/Config.in b/package/xml-security-c/Config.in
index 4c01855292..81d945f23d 100644
--- a/package/xml-security-c/Config.in
+++ b/package/xml-security-c/Config.in
@@ -12,5 +12,5 @@ config BR2_PACKAGE_XML_SECURITY_C
 	  https://santuario.apache.org/cindex.html
 
 comment "xml-security-c needs a toolchain w/ C++, wchar, gcc >= 4.7"
-	depends on !BR2_INSTALL_LIBSTDCPP || !BR2_USE_WCHAR ||
+	depends on !BR2_INSTALL_LIBSTDCPP || !BR2_USE_WCHAR || \
 		!BR2_TOOLCHAIN_GCC_AT_LEAST_4_7