Don't use -Werror because newer compilers introduce newer warnings.

Upstream-Status: Inappropriate [https://github.com/rhboot/efivar/issues/131]
Signed-off-by: Ross Burton <ross.burton@intel.com>

diff --git a/gcc.specs b/gcc.specs
index 45d43d1..1baf11a 100644
--- a/gcc.specs
+++ b/gcc.specs
@@ -2,7 +2,7 @@
 + -D_GNU_SOURCE
 
 *efivar_cpp_options:
- -Werror -Wall -std=gnu11 -Wextra
+ -Wall -std=gnu11 -Wextra
 
 *cpp_options:
 + %(efivar_cpp_options)