build: fix checks for GCC11

Fedora 34 already uses GCC11.

Reported-by: Marcin Juszkiewicz <[email protected]>
Signed-off-by: Petr Štetiar <[email protected]>

include/prereq-build.mk

@@ -26,8 +26,8 @@ $(eval $(call TestHostCommand,proper-umask, \
 ifndef IB
 $(eval $(call SetupHostCommand,gcc, \
 	Please install the GNU C Compiler (gcc) 6 or later, \
-	$(CC) -dumpversion | grep -E '^([6-9]\.?|10\.?)', \
-	gcc -dumpversion | grep -E '^([6-9]\.?|10\.?)', \
+	$(CC) -dumpversion | grep -E '^([6-9]\.?|1[0-9]\.?)', \
+	gcc -dumpversion | grep -E '^([6-9]\.?|1[0-9]\.?)', \
 	gcc --version | grep -E 'Apple.(LLVM|clang)' ))
 
 $(eval $(call TestHostCommand,working-gcc, \
@@ -38,8 +38,8 @@ $(eval $(call TestHostCommand,working-gcc, \
 
 $(eval $(call SetupHostCommand,g++, \
 	Please install the GNU C++ Compiler (g++) 6 or later, \
-	$(CXX) -dumpversion | grep -E '^([6-9]\.?|10\.?)', \
-	g++ -dumpversion | grep -E '^([6-9]\.?|10\.?)', \
+	$(CXX) -dumpversion | grep -E '^([6-9]\.?|1[0-9]\.?)', \
+	g++ -dumpversion | grep -E '^([6-9]\.?|1[0-9]\.?)', \
 	g++ --version | grep -E 'Apple.(LLVM|clang)' ))
 
 $(eval $(call TestHostCommand,working-g++, \